[SOLVED] qemu virtual router

eom.dev · 2022-03-02 22:00:42

I am trying to run the Arch Linux router described in the wiki using qemu, but the guest does not seem to be assigning IP addresses as expected. The hypervisor has two network ports, eno1np0 and eno2np1, connected to nothing and the internet respectively. My goal is to create a bridge for each of these, first to provide internet to the router, then to provide a switch for a lan of virtual machines. To avoid losing network connection on the host, I am not setting eno2np1's master to the respective bridge during testing. When I launch the VM, I am expecting it to assign an IP address to eno1np0, which would be used to ssh into the guest for further configuration; however, this does not happen, and the physical interface only has the inet6 address that appears to be assigned from the bridge, rather than the server.
Here are the router configuration files, which I keep in a git repository under /usr/local/src that has soft links to all of the necessary locations:
I am using systemd.network to configure the devices:

10-assign-tp-7e0ff89eaa2f-name.link

[Match]
MACAddress=8d:9e:df:4d:c2:6c 

[Link]
Description=tp-7e0ff89eaa2f name assignment
Name=tp-7e0ff89eaa2f

15-assign-tp-be05ee21d998-name.link

[Match]
MACAddress=05:cd:6d:80:0a:51

[Link]
Description=tp-be05ee21d998 name assignment
Name=tp-be05ee21d998

20-configure-tp-7e0ff89eaa2f.link

[Match]
Name=tp-7e0ff89eaa2f

[Network]
Address=10.1.10.9/24
Gateway=10.1.10.1
DNS=10.1.10.1

25-configure-tp-be05ee21d998.link

[Match]
Name=tp-be05ee21d998

[Network]
DHCP=yes

30-ipforward.conf

net.ipv4.ip_forward=1
net.ipv6.conf.default.forwarding=1
net.ipv6.conf.all.forwarding=1

iptables.rules

# Generated by iptables-save v1.8.7 on Thu Mar  3 20:52:01 2022
*filter
:INPUT ACCEPT [37:2124]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [21:1804]
-A FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
-A FORWARD -i tp-7e0ff89eaa2f -o tp-be05ee21d998 -j ACCEPT
COMMIT
# Completed on Thu Mar  3 20:52:01 2022
# Generated by iptables-save v1.8.7 on Thu Mar  3 20:52:01 2022
*nat
:PREROUTING ACCEPT [0:0]
:INPUT ACCEPT [0:0]
:OUTPUT ACCEPT [1:124]
:POSTROUTING ACCEPT [1:124]
-A POSTROUTING -o tp-be05ee21d998 -j MASQUERADE
COMMIT
# Completed on Thu Mar  3 20:52:01 2022

dnsmasq.conf (this one is long - I've included the complete file, but the only fields that differ from the default are those described in the wiki)

# Configuration file for dnsmasq.
#
# Format is one option per line, legal options are the same
# as the long options legal on the command line. See
# "/usr/sbin/dnsmasq --help" or "man 8 dnsmasq" for details.

# Listen on this specific port instead of the standard DNS port
# (53). Setting this to zero completely disables DNS function,
# leaving only DHCP and/or TFTP.
#port=5353

# The following two options make you a better netizen, since they
# tell dnsmasq to filter out queries which the public DNS cannot
# answer, and which load the servers (especially the root servers)
# unnecessarily. If you have a dial-on-demand link they also stop
# these requests from bringing up the link unnecessarily.

# Never forward plain names (without a dot or domain part)
#domain-needed
# Never forward addresses in the non-routed address spaces.
#bogus-priv

# Uncomment these to enable DNSSEC validation and caching:
# (Requires dnsmasq to be built with DNSSEC option.)
#conf-file=/usr/share/dnsmasq/trust-anchors.conf
#dnssec

# Replies which are not DNSSEC signed may be legitimate, because the domain
# is unsigned, or may be forgeries. Setting this option tells dnsmasq to
# check that an unsigned reply is OK, by finding a secure proof that a DS 
# record somewhere between the root and the domain does not exist. 
# The cost of setting this is that even queries in unsigned domains will need
# one or more extra DNS queries to verify.
#dnssec-check-unsigned

# Uncomment this to filter useless windows-originated DNS requests
# which can trigger dial-on-demand links needlessly.
# Note that (amongst other things) this blocks all SRV requests,
# so don't use it if you use eg Kerberos, SIP, XMMP or Google-talk.
# This option only affects forwarding, SRV records originating for
# dnsmasq (via srv-host= lines) are not suppressed by it.
#filterwin2k

# Change this line if you want dns to get its upstream servers from
# somewhere other that /etc/resolv.conf
#resolv-file=

# By  default,  dnsmasq  will  send queries to any of the upstream
# servers it knows about and tries to favour servers to are  known
# to  be  up.  Uncommenting this forces dnsmasq to try each query
# with  each  server  strictly  in  the  order  they   appear   in
# /etc/resolv.conf
#strict-order

# If you don't want dnsmasq to read /etc/resolv.conf or any other
# file, getting its servers from this file instead (see below), then
# uncomment this.
#no-resolv

# If you don't want dnsmasq to poll /etc/resolv.conf or other resolv
# files for changes and re-read them then uncomment this.
#no-poll

# Add other name servers here, with domain specs if they are for
# non-public domains.
#server=/localnet/192.168.0.1

# Example of routing PTR queries to nameservers: this will send all
# address->name queries for 192.168.3/24 to nameserver 10.1.2.3
#server=/3.168.192.in-addr.arpa/10.1.2.3

# Add local-only domains here, queries in these domains are answered
# from /etc/hosts or DHCP only.
#local=/localnet/

# Add domains which you want to force to an IP address here.
# The example below send any host in double-click.net to a local
# web-server.
#address=/double-click.net/127.0.0.1

# --address (and --server) work with IPv6 addresses too.
#address=/www.thekelleys.org.uk/fe80::20d:60ff:fe36:f83

# Add the IPs of all queries to yahoo.com, google.com, and their
# subdomains to the vpn and search ipsets:
#ipset=/yahoo.com/google.com/vpn,search

# You can control how dnsmasq talks to a server: this forces
# queries to 10.1.2.3 to be routed via eth1
# server=10.1.2.3@eth1

# and this sets the source (ie local) address used to talk to
# 10.1.2.3 to 192.168.1.1 port 55 (there must be an interface with that
# IP on the machine, obviously).
# server=10.1.2.3@192.168.1.1#55

# If you want dnsmasq to change uid and gid to something other
# than the default, edit the following lines.
#user=
#group=

# If you want dnsmasq to listen for DHCP and DNS requests only on
# specified interfaces (and the loopback) give the name of the
# interface (eg eth0) here.
# Repeat the line for more than one interface.
interface=tp-7e0ff89eaa2f
# Or you can specify which interface _not_ to listen on
#except-interface=
# Or which to listen on by address (remember to include 127.0.0.1 if
# you use this.)
#listen-address=
# If you want dnsmasq to provide only DNS service on an interface,
# configure it as shown above, and then use the following line to
# disable DHCP and TFTP on it.
#no-dhcp-interface=

# On systems which support it, dnsmasq binds the wildcard address,
# even when it is listening on only some interfaces. It then discards
# requests that it shouldn't reply to. This has the advantage of
# working even when interfaces come and go and change address. If you
# want dnsmasq to really bind only the interfaces it is listening on,
# uncomment this option. About the only time you may need this is when
# running another nameserver on the same machine.
#bind-interfaces

# If you don't want dnsmasq to read /etc/hosts, uncomment the
# following line.
#no-hosts
# or if you want it to read another file, as well as /etc/hosts, use
# this.
#addn-hosts=/etc/banner_add_hosts

# Set this (and domain: see below) if you want to have a domain
# automatically added to simple names in a hosts-file.
expand-hosts

# Set the domain for dnsmasq. this is optional, but if it is set, it
# does the following things.
# 1) Allows DHCP hosts to have fully qualified domain names, as long
#     as the domain part matches this setting.
# 2) Sets the "domain" DHCP option thereby potentially setting the
#    domain of all systems configured by DHCP
# 3) Provides the domain part for "expand-hosts"
domain=lan.eom.dev

# Set a different domain for a particular subnet
#domain=wireless.thekelleys.org.uk,192.168.2.0/24

# Same idea, but range rather then subnet
#domain=reserved.thekelleys.org.uk,192.68.3.100,192.168.3.200

# Uncomment this to enable the integrated DHCP server, you need
# to supply the range of addresses available for lease and optionally
# a lease time. If you have more than one network, you will need to
# repeat this for each network on which you want to supply DHCP
# service.
dhcp-range=10.0.0.2,10.0.0.255,255.255.255.0,1h

# This is an example of a DHCP range where the netmask is given. This
# is needed for networks we reach the dnsmasq DHCP server via a relay
# agent. If you don't know what a DHCP relay agent is, you probably
# don't need to worry about this.
#dhcp-range=192.168.0.50,192.168.0.150,255.255.255.0,12h

# This is an example of a DHCP range which sets a tag, so that
# some DHCP options may be set only for this network.
#dhcp-range=set:red,192.168.0.50,192.168.0.150

# Use this DHCP range only when the tag "green" is set.
#dhcp-range=tag:green,192.168.0.50,192.168.0.150,12h

# Specify a subnet which can't be used for dynamic address allocation,
# is available for hosts with matching --dhcp-host lines. Note that
# dhcp-host declarations will be ignored unless there is a dhcp-range
# of some type for the subnet in question.
# In this case the netmask is implied (it comes from the network
# configuration on the machine running dnsmasq) it is possible to give
# an explicit netmask instead.
#dhcp-range=192.168.0.0,static

# Enable DHCPv6. Note that the prefix-length does not need to be specified
# and defaults to 64 if missing/
#dhcp-range=1234::2, 1234::500, 64, 12h

# Do Router Advertisements, BUT NOT DHCP for this subnet.
#dhcp-range=1234::, ra-only 

# Do Router Advertisements, BUT NOT DHCP for this subnet, also try and
# add names to the DNS for the IPv6 address of SLAAC-configured dual-stack 
# hosts. Use the DHCPv4 lease to derive the name, network segment and 
# MAC address and assume that the host will also have an
# IPv6 address calculated using the SLAAC algorithm.
#dhcp-range=1234::, ra-names

# Do Router Advertisements, BUT NOT DHCP for this subnet.
# Set the lifetime to 46 hours. (Note: minimum lifetime is 2 hours.)
#dhcp-range=1234::, ra-only, 48h

# Do DHCP and Router Advertisements for this subnet. Set the A bit in the RA
# so that clients can use SLAAC addresses as well as DHCP ones.
#dhcp-range=1234::2, 1234::500, slaac

# Do Router Advertisements and stateless DHCP for this subnet. Clients will
# not get addresses from DHCP, but they will get other configuration information.
# They will use SLAAC for addresses.
#dhcp-range=1234::, ra-stateless

# Do stateless DHCP, SLAAC, and generate DNS names for SLAAC addresses
# from DHCPv4 leases.
#dhcp-range=1234::, ra-stateless, ra-names

# Do router advertisements for all subnets where we're doing DHCPv6
# Unless overridden by ra-stateless, ra-names, et al, the router 
# advertisements will have the M and O bits set, so that the clients
# get addresses and configuration from DHCPv6, and the A bit reset, so the 
# clients don't use SLAAC addresses.
#enable-ra

# Supply parameters for specified hosts using DHCP. There are lots
# of valid alternatives, so we will give examples of each. Note that
# IP addresses DO NOT have to be in the range given above, they just
# need to be on the same network. The order of the parameters in these
# do not matter, it's permissible to give name, address and MAC in any
# order.

# Always allocate the host with Ethernet address 11:22:33:44:55:66
# The IP address 192.168.0.60
#dhcp-host=11:22:33:44:55:66,192.168.0.60

# Always set the name of the host with hardware address
# 11:22:33:44:55:66 to be "fred"
#dhcp-host=11:22:33:44:55:66,fred

# Always give the host with Ethernet address 11:22:33:44:55:66
# the name fred and IP address 192.168.0.60 and lease time 45 minutes
#dhcp-host=11:22:33:44:55:66,fred,192.168.0.60,45m

# Give a host with Ethernet address 11:22:33:44:55:66 or
# 12:34:56:78:90:12 the IP address 192.168.0.60. Dnsmasq will assume
# that these two Ethernet interfaces will never be in use at the same
# time, and give the IP address to the second, even if it is already
# in use by the first. Useful for laptops with wired and wireless
# addresses.
#dhcp-host=11:22:33:44:55:66,12:34:56:78:90:12,192.168.0.60

# Give the machine which says its name is "bert" IP address
# 192.168.0.70 and an infinite lease
#dhcp-host=bert,192.168.0.70,infinite

# Always give the host with client identifier 01:02:02:04
# the IP address 192.168.0.60
#dhcp-host=id:01:02:02:04,192.168.0.60

# Always give the InfiniBand interface with hardware address
# 80:00:00:48:fe:80:00:00:00:00:00:00:f4:52:14:03:00:28:05:81 the
# ip address 192.168.0.61. The client id is derived from the prefix
# ff:00:00:00:00:00:02:00:00:02:c9:00 and the last 8 pairs of
# hex digits of the hardware address.
#dhcp-host=id:ff:00:00:00:00:00:02:00:00:02:c9:00:f4:52:14:03:00:28:05:81,192.168.0.61

# Always give the host with client identifier "marjorie"
# the IP address 192.168.0.60
#dhcp-host=id:marjorie,192.168.0.60

# Enable the address given for "judge" in /etc/hosts
# to be given to a machine presenting the name "judge" when
# it asks for a DHCP lease.
#dhcp-host=judge

# Never offer DHCP service to a machine whose Ethernet
# address is 11:22:33:44:55:66
#dhcp-host=11:22:33:44:55:66,ignore

# Ignore any client-id presented by the machine with Ethernet
# address 11:22:33:44:55:66. This is useful to prevent a machine
# being treated differently when running under different OS's or
# between PXE boot and OS boot.
#dhcp-host=11:22:33:44:55:66,id:*

# Send extra options which are tagged as "red" to
# the machine with Ethernet address 11:22:33:44:55:66
#dhcp-host=11:22:33:44:55:66,set:red

# Send extra options which are tagged as "red" to
# any machine with Ethernet address starting 11:22:33:
#dhcp-host=11:22:33:*:*:*,set:red

# Give a fixed IPv6 address and name to client with 
# DUID 00:01:00:01:16:d2:83:fc:92:d4:19:e2:d8:b2
# Note the MAC addresses CANNOT be used to identify DHCPv6 clients.
# Note also that the [] around the IPv6 address are obligatory.
#dhcp-host=id:00:01:00:01:16:d2:83:fc:92:d4:19:e2:d8:b2, fred, [1234::5] 

# Ignore any clients which are not specified in dhcp-host lines
# or /etc/ethers. Equivalent to ISC "deny unknown-clients".
# This relies on the special "known" tag which is set when
# a host is matched.
#dhcp-ignore=tag:!known

# Send extra options which are tagged as "red" to any machine whose
# DHCP vendorclass string includes the substring "Linux"
#dhcp-vendorclass=set:red,Linux

# Send extra options which are tagged as "red" to any machine one
# of whose DHCP userclass strings includes the substring "accounts"
#dhcp-userclass=set:red,accounts

# Send extra options which are tagged as "red" to any machine whose
# MAC address matches the pattern.
#dhcp-mac=set:red,00:60:8C:*:*:*

# If this line is uncommented, dnsmasq will read /etc/ethers and act
# on the ethernet-address/IP pairs found there just as if they had
# been given as --dhcp-host options. Useful if you keep
# MAC-address/host mappings there for other purposes.
#read-ethers

# Send options to hosts which ask for a DHCP lease.
# See RFC 2132 for details of available options.
# Common options can be given to dnsmasq by name:
# run "dnsmasq --help dhcp" to get a list.
# Note that all the common settings, such as netmask and
# broadcast address, DNS server and default route, are given
# sane defaults by dnsmasq. You very likely will not need
# any dhcp-options. If you use Windows clients and Samba, there
# are some options which are recommended, they are detailed at the
# end of this section.

# Override the default route supplied by dnsmasq, which assumes the
# router is the same machine as the one running dnsmasq.
#dhcp-option=3,1.2.3.4

# Do the same thing, but using the option name
#dhcp-option=option:router,1.2.3.4

# Override the default route supplied by dnsmasq and send no default
# route at all. Note that this only works for the options sent by
# default (1, 3, 6, 12, 28) the same line will send a zero-length option
# for all other option numbers.
#dhcp-option=3

# Set the NTP time server addresses to 192.168.0.4 and 10.10.0.5
#dhcp-option=option:ntp-server,192.168.0.4,10.10.0.5

# Send DHCPv6 option. Note [] around IPv6 addresses.
#dhcp-option=option6:dns-server,[1234::77],[1234::88]

# Send DHCPv6 option for namservers as the machine running 
# dnsmasq and another.
#dhcp-option=option6:dns-server,[::],[1234::88]

# Ask client to poll for option changes every six hours. (RFC4242)
#dhcp-option=option6:information-refresh-time,6h

# Set option 58 client renewal time (T1). Defaults to half of the
# lease time if not specified. (RFC2132)
#dhcp-option=option:T1,1m

# Set option 59 rebinding time (T2). Defaults to 7/8 of the
# lease time if not specified. (RFC2132)
#dhcp-option=option:T2,2m

# Set the NTP time server address to be the same machine as
# is running dnsmasq
#dhcp-option=42,0.0.0.0

# Set the NIS domain name to "welly"
#dhcp-option=40,welly

# Set the default time-to-live to 50
#dhcp-option=23,50

# Set the "all subnets are local" flag
#dhcp-option=27,1

# Send the etherboot magic flag and then etherboot options (a string).
#dhcp-option=128,e4:45:74:68:00:00
#dhcp-option=129,NIC=eepro100

# Specify an option which will only be sent to the "red" network
# (see dhcp-range for the declaration of the "red" network)
# Note that the tag: part must precede the option: part.
#dhcp-option = tag:red, option:ntp-server, 192.168.1.1

# The following DHCP options set up dnsmasq in the same way as is specified
# for the ISC dhcpcd in
# http://www.samba.org/samba/ftp/docs/textdocs/DHCP-Server-Configuration.txt
# adapted for a typical dnsmasq installation where the host running
# dnsmasq is also the host running samba.
# you may want to uncomment some or all of them if you use
# Windows clients and Samba.
#dhcp-option=19,0           # option ip-forwarding off
#dhcp-option=44,0.0.0.0     # set netbios-over-TCP/IP nameserver(s) aka WINS server(s)
#dhcp-option=45,0.0.0.0     # netbios datagram distribution server
#dhcp-option=46,8           # netbios node type

# Send an empty WPAD option. This may be REQUIRED to get windows 7 to behave.
#dhcp-option=252,"\n"

# Send RFC-3397 DNS domain search DHCP option. WARNING: Your DHCP client
# probably doesn't support this......
#dhcp-option=option:domain-search,eng.apple.com,marketing.apple.com

# Send RFC-3442 classless static routes (note the netmask encoding)
#dhcp-option=121,192.168.1.0/24,1.2.3.4,10.0.0.0/8,5.6.7.8

# Send vendor-class specific options encapsulated in DHCP option 43.
# The meaning of the options is defined by the vendor-class so
# options are sent only when the client supplied vendor class
# matches the class given here. (A substring match is OK, so "MSFT"
# matches "MSFT" and "MSFT 5.0"). This example sets the
# mtftp address to 0.0.0.0 for PXEClients.
#dhcp-option=vendor:PXEClient,1,0.0.0.0

# Send microsoft-specific option to tell windows to release the DHCP lease
# when it shuts down. Note the "i" flag, to tell dnsmasq to send the
# value as a four-byte integer - that's what microsoft wants. See
# http://technet2.microsoft.com/WindowsServer/en/library/a70f1bb7-d2d4-49f0-96d6-4b7414ecfaae1033.mspx?mfr=true
#dhcp-option=vendor:MSFT,2,1i

# Send the Encapsulated-vendor-class ID needed by some configurations of
# Etherboot to allow is to recognise the DHCP server.
#dhcp-option=vendor:Etherboot,60,"Etherboot"

# Send options to PXELinux. Note that we need to send the options even
# though they don't appear in the parameter request list, so we need
# to use dhcp-option-force here.
# See http://syslinux.zytor.com/pxe.php#special for details.
# Magic number - needed before anything else is recognised
#dhcp-option-force=208,f1:00:74:7e
# Configuration file name
#dhcp-option-force=209,configs/common
# Path prefix
#dhcp-option-force=210,/tftpboot/pxelinux/files/
# Reboot time. (Note 'i' to send 32-bit value)
#dhcp-option-force=211,30i

# Set the boot filename for netboot/PXE. You will only need
# this if you want to boot machines over the network and you will need
# a TFTP server; either dnsmasq's built-in TFTP server or an
# external one. (See below for how to enable the TFTP server.)
#dhcp-boot=pxelinux.0

# The same as above, but use custom tftp-server instead machine running dnsmasq
#dhcp-boot=pxelinux,server.name,192.168.1.100

# Boot for iPXE. The idea is to send two different
# filenames, the first loads iPXE, and the second tells iPXE what to
# load. The dhcp-match sets the ipxe tag for requests from iPXE.
#dhcp-boot=undionly.kpxe
#dhcp-match=set:ipxe,175 # iPXE sends a 175 option.
#dhcp-boot=tag:ipxe,http://boot.ipxe.org/demo/boot.php

# Encapsulated options for iPXE. All the options are
# encapsulated within option 175
#dhcp-option=encap:175, 1, 5b         # priority code
#dhcp-option=encap:175, 176, 1b       # no-proxydhcp
#dhcp-option=encap:175, 177, string   # bus-id
#dhcp-option=encap:175, 189, 1b       # BIOS drive code
#dhcp-option=encap:175, 190, user     # iSCSI username
#dhcp-option=encap:175, 191, pass     # iSCSI password

# Test for the architecture of a netboot client. PXE clients are
# supposed to send their architecture as option 93. (See RFC 4578)
#dhcp-match=peecees, option:client-arch, 0 #x86-32
#dhcp-match=itanics, option:client-arch, 2 #IA64
#dhcp-match=hammers, option:client-arch, 6 #x86-64
#dhcp-match=mactels, option:client-arch, 7 #EFI x86-64

# Do real PXE, rather than just booting a single file, this is an
# alternative to dhcp-boot.
#pxe-prompt="What system shall I netboot?"
# or with timeout before first available action is taken:
#pxe-prompt="Press F8 for menu.", 60

# Available boot services. for PXE.
#pxe-service=x86PC, "Boot from local disk"

# Loads <tftp-root>/pxelinux.0 from dnsmasq TFTP server.
#pxe-service=x86PC, "Install Linux", pxelinux

# Loads <tftp-root>/pxelinux.0 from TFTP server at 1.2.3.4.
# Beware this fails on old PXE ROMS.
#pxe-service=x86PC, "Install Linux", pxelinux, 1.2.3.4

# Use bootserver on network, found my multicast or broadcast.
#pxe-service=x86PC, "Install windows from RIS server", 1

# Use bootserver at a known IP address.
#pxe-service=x86PC, "Install windows from RIS server", 1, 1.2.3.4

# If you have multicast-FTP available,
# information for that can be passed in a similar way using options 1
# to 5. See page 19 of
# http://download.intel.com/design/archives/wfm/downloads/pxespec.pdf


# Enable dnsmasq's built-in TFTP server
#enable-tftp

# Set the root directory for files available via FTP.
#tftp-root=/var/ftpd

# Do not abort if the tftp-root is unavailable
#tftp-no-fail

# Make the TFTP server more secure: with this set, only files owned by
# the user dnsmasq is running as will be send over the net.
#tftp-secure

# This option stops dnsmasq from negotiating a larger blocksize for TFTP
# transfers. It will slow things down, but may rescue some broken TFTP
# clients.
#tftp-no-blocksize

# Set the boot file name only when the "red" tag is set.
#dhcp-boot=tag:red,pxelinux.red-net

# An example of dhcp-boot with an external TFTP server: the name and IP
# address of the server are given after the filename.
# Can fail with old PXE ROMS. Overridden by --pxe-service.
#dhcp-boot=/var/ftpd/pxelinux.0,boothost,192.168.0.3

# If there are multiple external tftp servers having a same name
# (using /etc/hosts) then that name can be specified as the
# tftp_servername (the third option to dhcp-boot) and in that
# case dnsmasq resolves this name and returns the resultant IP
# addresses in round robin fashion. This facility can be used to
# load balance the tftp load among a set of servers.
#dhcp-boot=/var/ftpd/pxelinux.0,boothost,tftp_server_name

# Set the limit on DHCP leases, the default is 150
#dhcp-lease-max=150

# The DHCP server needs somewhere on disk to keep its lease database.
# This defaults to a sane location, but if you want to change it, use
# the line below.
#dhcp-leasefile=/var/lib/misc/dnsmasq.leases

# Set the DHCP server to authoritative mode. In this mode it will barge in
# and take over the lease for any client which broadcasts on the network,
# whether it has a record of the lease or not. This avoids long timeouts
# when a machine wakes up on a new network. DO NOT enable this if there's
# the slightest chance that you might end up accidentally configuring a DHCP
# server for your campus/company accidentally. The ISC server uses
# the same option, and this URL provides more information:
# http://www.isc.org/files/auth.html
#dhcp-authoritative

# Set the DHCP server to enable DHCPv4 Rapid Commit Option per RFC 4039.
# In this mode it will respond to a DHCPDISCOVER message including a Rapid Commit
# option with a DHCPACK including a Rapid Commit option and fully committed address
# and configuration information. This must only be enabled if either the server is 
# the only server for the subnet, or multiple servers are present and they each
# commit a binding for all clients.
#dhcp-rapid-commit

# Run an executable when a DHCP lease is created or destroyed.
# The arguments sent to the script are "add" or "del",
# then the MAC address, the IP address and finally the hostname
# if there is one.
#dhcp-script=/bin/echo

# Set the cachesize here.
#cache-size=150

# If you want to disable negative caching, uncomment this.
#no-negcache

# Normally responses which come from /etc/hosts and the DHCP lease
# file have Time-To-Live set as zero, which conventionally means
# do not cache further. If you are happy to trade lower load on the
# server for potentially stale date, you can set a time-to-live (in
# seconds) here.
#local-ttl=

# If you want dnsmasq to detect attempts by Verisign to send queries
# to unregistered .com and .net hosts to its sitefinder service and
# have dnsmasq instead return the correct NXDOMAIN response, uncomment
# this line. You can add similar lines to do the same for other
# registries which have implemented wildcard A records.
#bogus-nxdomain=64.94.110.11

# If you want to fix up DNS results from upstream servers, use the
# alias option. This only works for IPv4.
# This alias makes a result of 1.2.3.4 appear as 5.6.7.8
#alias=1.2.3.4,5.6.7.8
# and this maps 1.2.3.x to 5.6.7.x
#alias=1.2.3.0,5.6.7.0,255.255.255.0
# and this maps 192.168.0.10->192.168.0.40 to 10.0.0.10->10.0.0.40
#alias=192.168.0.10-192.168.0.40,10.0.0.0,255.255.255.0

# Change these lines if you want dnsmasq to serve MX records.

# Return an MX record named "maildomain.com" with target
# servermachine.com and preference 50
#mx-host=maildomain.com,servermachine.com,50

# Set the default target for MX records created using the localmx option.
#mx-target=servermachine.com

# Return an MX record pointing to the mx-target for all local
# machines.
#localmx

# Return an MX record pointing to itself for all local machines.
#selfmx

# Change the following lines if you want dnsmasq to serve SRV
# records.  These are useful if you want to serve ldap requests for
# Active Directory and other windows-originated DNS requests.
# See RFC 2782.
# You may add multiple srv-host lines.
# The fields are <name>,<target>,<port>,<priority>,<weight>
# If the domain part if missing from the name (so that is just has the
# service and protocol sections) then the domain given by the domain=
# config option is used. (Note that expand-hosts does not need to be
# set for this to work.)

# A SRV record sending LDAP for the example.com domain to
# ldapserver.example.com port 389
#srv-host=_ldap._tcp.example.com,ldapserver.example.com,389

# A SRV record sending LDAP for the example.com domain to
# ldapserver.example.com port 389 (using domain=)
#domain=example.com
#srv-host=_ldap._tcp,ldapserver.example.com,389

# Two SRV records for LDAP, each with different priorities
#srv-host=_ldap._tcp.example.com,ldapserver.example.com,389,1
#srv-host=_ldap._tcp.example.com,ldapserver.example.com,389,2

# A SRV record indicating that there is no LDAP server for the domain
# example.com
#srv-host=_ldap._tcp.example.com

# The following line shows how to make dnsmasq serve an arbitrary PTR
# record. This is useful for DNS-SD. (Note that the
# domain-name expansion done for SRV records _does_not
# occur for PTR records.)
#ptr-record=_http._tcp.dns-sd-services,"New Employee Page._http._tcp.dns-sd-services"

# Change the following lines to enable dnsmasq to serve TXT records.
# These are used for things like SPF and zeroconf. (Note that the
# domain-name expansion done for SRV records _does_not
# occur for TXT records.)

#Example SPF.
#txt-record=example.com,"v=spf1 a -all"

#Example zeroconf
#txt-record=_http._tcp.example.com,name=value,paper=A4

# Provide an alias for a "local" DNS name. Note that this _only_ works
# for targets which are names from DHCP or /etc/hosts. Give host
# "bert" another name, bertrand
#cname=bertand,bert

# For debugging purposes, log each DNS query as it passes through
# dnsmasq.
#log-queries

# Log lots of extra information about DHCP transactions.
#log-dhcp

# Include another lot of configuration options.
#conf-file=/etc/dnsmasq.more.conf
#conf-dir=/etc/dnsmasq.d

# Include all the files in a directory except those ending in .bak
#conf-dir=/etc/dnsmasq.d,.bak

# Include all files in a directory which end in .conf
#conf-dir=/etc/dnsmasq.d/,*.conf

# If a DHCP client claims that its name is "wpad", ignore that.
# This fixes a security hole. see CERT Vulnerability VU#598349
#dhcp-name-match=set:wpad-ignore,wpad
#dhcp-ignore-names=tag:wpad-ignore

Here are the running services on the router:

$ systemctl --type=service

  UNIT                               LOAD   ACTIVE SUB     DESCRIPTION                                        
  dbus.service                       loaded active running D-Bus System Message Bus
  dhcpcd.service                     loaded active running dhcpcd on all interfaces
  dnsmasq.service                    loaded active running dnsmasq - A lightweight DHCP and caching DNS server
  getty@tty1.service                 loaded active running Getty on tty1
  iptables.service                   loaded active exited  IPv4 Packet Filtering Framework
  kmod-static-nodes.service          loaded active exited  Create List of Static Device Nodes
  sshd.service                       loaded active running OpenSSH Daemon
  systemd-journal-flush.service      loaded active exited  Flush Journal to Persistent Storage
  systemd-journald.service           loaded active running Journal Service
  systemd-logind.service             loaded active running User Login Management
  systemd-network-generator.service  loaded active exited  Generate network units from Kernel command line
  systemd-networkd.service           loaded active running Network Configuration
  systemd-random-seed.service        loaded active exited  Load/Save Random Seed
  systemd-remount-fs.service         loaded active exited  Remount Root and Kernel File Systems
  systemd-sysctl.service             loaded active exited  Apply Kernel Variables
  systemd-tmpfiles-setup-dev.service loaded active exited  Create Static Device Nodes in /dev
  systemd-tmpfiles-setup.service     loaded active exited  Create Volatile Files and Directories
  systemd-udev-trigger.service       loaded active exited  Coldplug All udev Devices
  systemd-udevd.service              loaded active running Rule-based Manager for Device Events and Files
  systemd-update-utmp.service        loaded active exited  Record System Boot/Shutdown in UTMP
  systemd-user-sessions.service      loaded active exited  Permit User Sessions
  user-runtime-dir@0.service         loaded active exited  User Runtime Directory /run/user/0
  user@0.service                     loaded active running User Manager for UID 0

(I've tried this with and without dhcpcd running with the same result - I assume dhcpcd is needed)

On QEMU's side, I have a few scripts for ifup and launching the virtual machine:

tp-7e0ff89eaa2f-ifup.sh

if [[ $1 == "tp-7e0ff89eaa2f" ]]
then
        ip link set tp-7e0ff89eaa2f up
        sleep 1
        ip link set tp-7e0ff89eaa2f master br-e6b86139b3d7
        ip link set eno1np0 up
        sleep 1
        ip link set eno1np0 master br-e6b86139b3d7
        ip link set br-e6b86139b3d7 up
        exit 0
else
        echo "configuration error"
        exit 1
fi

tp-be05ee21d998-ifup.sh

if [[ $1 == "tp-be05ee21d998" ]]
then
        ip link set tp-be05ee21d998 up
        sleep 1
        ip link set tp-be05ee21d998 master br-6457cd106f48
        #ip link set eno2np1 down <--- currently disabled for testing
        #ip link set eno2np1 master br-6457cd106f48
        sleep 1
        #ip link set eno2np1 up
        ip link set br-6457cd106f48 up
        exit 0
else
        echo "configuration error"
        exit 1
fi

Finally, for starting the vm, run.sh:

qemu-system-x86_64 -drive file=virtual-disk-a40c34f875e1,format=raw -enable-kvm -m 2G -netdev tap,id=tp-7e0ff89eaa2f,ifname=tp-7e0ff89eaa2f,script=qemu/tp-7e0ff89eaa2f-ifup.sh -device e1000,netdev=tp-7e0ff89eaa2f,mac=8d:9e:df:4d:c2:6c -netdev tap,id=tp-be05ee21d998,ifname=tp-be05ee21d998,script=qemu/tp-be05ee21d998-ifup.sh -device e1000,netdev=tp-be05ee21d998,mac=05:cd:6d:80:0a:51

which results in the following IP links:

$ ip a

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000                                                                                       
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00                                                                                                                         
    inet 127.0.0.1/8 scope host lo                                                                                                                                                
       valid_lft forever preferred_lft forever                                                                                                                                    
    inet6 ::1/128 scope host                                                                                                                                                      
       valid_lft forever preferred_lft forever                                                                                                                                    
2: eno1np0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq master br-e6b86139b3d7 state DOWN group default qlen 1000                                                       
    link/ether ec:2a:72:15:a2:20 brd ff:ff:ff:ff:ff:ff                                                                                                                            
    altname enp23s0f0np0                                                                                                                                                          
3: eno2np1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000                                                                                  
    link/ether ec:2a:72:15:a2:21 brd ff:ff:ff:ff:ff:ff                                                                                                                            
    altname enp23s0f1np1                                                                                                                                                          
    inet 192.168.1.167/24 brd 192.168.1.255 scope global dynamic noprefixroute eno2np1                                                                                            
       valid_lft 82134sec preferred_lft 71334sec    
    inet6 2600:1700:760:2120::1c/128 scope global dynamic noprefixroute 
       valid_lft 2945sec preferred_lft 2945sec
    inet6 fda5:d6a8:799f:4b5e:8a2a:3946:9ad9:2136/64 scope global dynamic mngtmpaddr noprefixroute 
       valid_lft 1613sec preferred_lft 158sec
    inet6 2600:1700:760:2120:2af6:d310:9f10:e9b0/64 scope global dynamic mngtmpaddr noprefixroute 
       valid_lft 3413sec preferred_lft 3413sec
    inet6 fe80::98d9:20a3:613:3a22/64 scope link 
       valid_lft forever preferred_lft forever
4: br-e6b86139b3d7: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 12:07:cf:14:bd:43 brd ff:ff:ff:ff:ff:ff
    inet6 fe80::1007:cfff:fe14:bd43/64 scope link 
       valid_lft forever preferred_lft forever
5: br-6457cd106f48: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether ee:b6:40:3e:7e:0c brd ff:ff:ff:ff:ff:ff
    inet6 fe80::ecb6:40ff:fe3e:7e0c/64 scope link 
       valid_lft forever preferred_lft forever
12: tp-7e0ff89eaa2f: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel master br-e6b86139b3d7 state UNKNOWN group default qlen 1000
    link/ether 0e:54:fa:91:1a:87 brd ff:ff:ff:ff:ff:ff
    inet6 fe80::c54:faff:fe91:1a87/64 scope link 
       valid_lft forever preferred_lft forever
13: tp-be05ee21d998: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel master br-6457cd106f48 state UNKNOWN group default qlen 1000
    link/ether a2:ce:bd:81:e5:4a brd ff:ff:ff:ff:ff:ff
    inet6 fe80::a0ce:bdff:fe81:e54a/64 scope link 
       valid_lft forever preferred_lft forever

This is difficult to debug, as I am unable to connect to the server when running it in this mode. I can create a user network for ssh, but that doesn't simulate the needed devices. Interestingly, if I complete the design by adding internet to the bridge, my home router shows a machine being connected on ethernet1, but it never gets an IP address.
I'm not sure what could be causing the problem, and am having trouble discerning a way to debug. I would appreciate advice on either front!
Thank you for reading.

Last edited by eom.dev (2022-03-05 19:00:55)

eom.dev · 2022-03-04 14:00:04

I've added additional details, but it doesn't seem like this is the appropriate channel for this post - would it be possible to move it?

ewaller · 2022-03-04 15:53:47

eom.dev wrote:

I've added additional details, but it doesn't seem like this is the appropriate channel for this post - would it be possible to move it?

Where to?

Also, if you make a request using the report link a moderators are notified so you don't have to wait for one of us to stumble upon a post with the request.

eom.dev · 2022-03-04 16:14:18

Thank you, Networking, Server, and Protection seems right to me. I'll use the report link in the future

ewaller · 2022-03-04 16:26:35

Moved by request. And, you are welcome.

-thc · 2022-03-04 23:27:23

I try to summarize your setup - correct me if I got it wrong.

You have two physical network interfaces (eno1np0 and eno2np1 - both with Dell MACs).
You have two virtual network interfaces (tp-7e0ff89eaa2f and tp-be05ee21d998 - both with weird MAC behavior).
You have two bridges (br-e6b86139b3d7 and br-6457cd106f48) - each binding one physical and one virtual together.

And here the trouble begins. A bridge binds two or more network interfaces together - on OSI Level 2. The bridge members lose their IP addresses (OSI Level 3) and cease to function as independent interfaces. I doubt dnsmasq works on a bridge member. An IP address can only be assigned to the bridge interface. Packet flow on the bridge level must be managed via ebtables - not iptables.

To sum it up - I think you misinterpreted a network bridge as a kind of virtual switch - which it isn't.
So there is some kind of misinterpretation.

Last edited by -thc (2022-03-05 07:44:57)

Tarqi · 2022-03-05 01:10:45

-thc wrote:

To sum it up - I think you misinterpreted a network bridge as a kind of virtual switch - which it isn't.

Sure it is. One might read https://wiki.archlinux.org/title/Network_bridge or https://developers.redhat.com/blog/2018 … ing#bridge or [insert google stuff here]...

eom.dev · 2022-03-05 03:00:01

A quick update after working on this for a day: there were a number of problems with my configurations and understanding of what I was seeing. First of all, the virtual machine does have an IP address, clearly labeled in the

ip a

output - it is an IPv6 address, which I was not expecting. If I finish the configuration by connecting eno2np1 to the bridge, both devices appear on my network (oddly my router gives IPv6 to both guest and host, and IPv4 to guest). I can ping, ssh, and do what I need to on the router using those IPv6 addresses after reconnecting via ssh to the new hypervisor address.

From there, my configuration of the systems-network link files was incorrect. I was splitting each part of the interface config into separate files, when I should have been setting the name and static/dynamic ip assignment in a single file per network device. So now I am able to connect to the machine via ssh over the eno1np2 connection and I am working on setting up the IP tables rules for the last leg of this journey. I'll post the final configurations tomorrow once I get that part working - iptables and systems-network are throwing errors about not having IPv4.

There is a larger lesson to take away here: my mistake was that I tried to do too many things at once when I should have been more patient and built this VM one step at a time. By throwing all of these configurations on at once, I was left with a black box that was impossible to debug. I started making progress when I started the project over and took it one step at a time. First boot a VM on the tap interface, then configure the interface profiles with systemd, then iptables. Each step could be checked, debugged, and built upon.

eom.dev · 2022-03-05 14:28:52

I currently am thinking that the use of IPv4 vs v6 is causing the problems here. On the router, I have the systemd-network configured as shown below:

[Match]
MACAddress=17:27:e8:34:dc:28

[Link]
Description=onnet
Name=tp-09b31f56d003

[Network]
Address=10.1.10.9/24
Gateway=10.1.10.1
DNS=10.1.10.1

When I check the network interfaces on the server, I see that this device is down:

$ ip a

2: tp-a86608e02f4d: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000         
    link/ether 94:32:12:38:ab:6c brd ff:ff:ff:ff:ff:ff                                                                 
    inet 192.168.1.170/24 brd 192.168.1.255 scope global dynamic noprefixroute tp-a86608e02f4d                         
       valid_lft 86024sec preferred_lft 75224sec                                                                       
    inet6 2600:1700:760:2120::2b/128 scope global dynamic noprefixroute                                                
       valid_lft 3221sec preferred_lft 3221sec                                                                         
    inet6 fda5:d6a8:799f:4b5e:7804:860d:4843:e639/64 scope global dynamic mngtmpaddr noprefixroute                     
       valid_lft 1673sec preferred_lft 208sec                                                                          
    inet6 2600:1700:760:2120:10d1:741f:49f9:4892/64 scope global dynamic mngtmpaddr noprefixroute                      
       valid_lft 3473sec preferred_lft 3473sec                                                                         
    inet6 fe80::515e:a565:dcdb:e7a0/64 scope link                                                                      
       valid_lft forever preferred_lft forever                                                                        
3: tp-09b31f56d003: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000                     
    link/ether 17:27:e8:34:dc:28 brd ff:ff:ff:ff:ff:ff

I tried to bring it up manually, but am receiving an error message:

$ ip link set tp-09b31f56d003 up                                                     
RTNETLINK answers: Cannot assign requested address

The wiki says you can use an IPv6 address, and it describes how to generate a block for the address field, but I need to discern what gateway/dns fields. That, or I need to get IPv4 running...

Last edited by eom.dev (2022-03-05 14:33:32)

eom.dev · 2022-03-05 16:14:09

Well I've configured things so that no more errors are being thrown by the services, but devices on the LAN bridge are still not getting IPs from the virtual router. Here are the most up to date configurations:

10-tp-09b31f56d003-configuration.link

[Match]
MACAddress=DE:AD:BE:EF:73:2D

[Link]
Description=onnet
Name=tp-09b31f56d003

[Network]
Address=10.1.10.9/24
Gateway=10.1.10.1
DNS=10.1.10.1

20-tp-a86608e02f4d-configuration.link

[Match]
MACAddress=DE:AD:BE:EF:68:F9

[Link]
Description=offnet
Name=tp-a86608e02f4d

[Network]
DHCP=yes

30-ipforward.conf

net.ipv4.ip_forward=1
net.ipv6.conf.default.forwarding=1
net.ipv6.conf.all.forwarding=1

iptables.rules

# Generated by iptables-save v1.8.7 on Fri Mar  4 19:53:22 2022
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
-A FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
-A FORWARD -i tp-e241b85f9d32 -o tp-a86608e02f4d -j ACCEPT
COMMIT
# Completed on Fri Mar  4 19:53:22 2022
# Generated by iptables-save v1.8.7 on Fri Mar  4 19:53:22 2022
*nat
:PREROUTING ACCEPT [0:0]
:INPUT ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
:POSTROUTING ACCEPT [0:0]
-A POSTROUTING -o tp-a86608e02f4d -j MASQUERADE
COMMIT
# Completed on Fri Mar  4 19:53:22 2022

dnsmasq conf is unchanged

this script launches the virtual machine, largely it is as before, but now I have it assign an IP address to the bridge (which I am guessing should be the same as gateway in the static ip for systemd-networkd).

declare -A interfaces=(["br-ae6a881b3195"]="eno2np1" ["br-e241b85f9d32"]="eno1np0")
declare -A bridges=(["tp-a86608e02f4d"]="br-ae6a881b3195" ["tp-09b31f56d003"]="br-e241b85f9d32")
LAN="br-e241b85f9d32"
tap=$1

if [[ $(ip link show ${bridges[$tap]} 2> /dev/null) ]]
then
        ip link set ${interfaces[${bridges[$tap]}]} nomaster
        echo "installation-63086aae8735 | $(date +%Y-%m-%d) | $(date +%H:%M:%S.%N) │ qemu-ifup | disconnected physical interface from bridge | interface={{ ${interfaces[${bridges[$tap]}]} }}, bridge={{ ${bridges[$tap]} }}"
        ip link set ${bridges[$tap]} down
        sleep 1
        ip link del ${bridges[$tap]}
        echo "installation-63086aae8735 | $(date +%Y-%m-%d) | $(date +%H:%M:%S.%N) │ qemu-ifup | removed pre-existing bridge | bridge={{ ${bridges[$tap]} }}"
fi
ip link add name ${bridges[$tap]} type bridge
sleep 1
ip link set ${bridges[$tap]} up
if [[ ${bridges[$tap]} == $LAN ]]
then
        ip address add dev br-e241b85f9d32 10.1.10.1/24
fi
echo "installation-63086aae8735 | $(date +%Y-%m-%d) | $(date +%H:%M:%S.%N) │ | qemu-ifup | bridge created | bridge={{ ${bridges[$tap]} }}"
ip link set ${interfaces[${bridges[$tap]}]} master ${bridges[$tap]}
echo "installation-63086aae8735 | $(date +%Y-%m-%d) | $(date +%H:%M:%S.%N) │ qemu-ifup | connected physical interface to bridge | interface={{ ${interfaces[${bridges[$tap]}]} }} | bridge={{ ${bridges[$tap]} }}"
ip link set $tap up
ip link set $tap master ${bridges[$tap]}
echo "installation-63086aae8735 | $(date +%Y-%m-%d) | $(date +%H:%M:%S.%N) | qemu-ifup | connected tap to bridge | tap={{ $tap }} | bridge={{ ${bridges[$tap]} }}"

when executed, the results look like this:

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eno1np0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq master br-e241b85f9d32 state DOWN group default qlen 1000
    link/ether ec:2a:72:15:a2:20 brd ff:ff:ff:ff:ff:ff
    altname enp23s0f0np0
3: eno2np1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master br-ae6a881b3195 state UP group default qlen 1000
    link/ether ec:2a:72:15:a2:21 brd ff:ff:ff:ff:ff:ff
    altname enp23s0f1np1
    inet 192.168.1.167/24 brd 192.168.1.255 scope global dynamic noprefixroute eno2np1
       valid_lft 77287sec preferred_lft 66487sec
    inet6 fe80::98d9:20a3:613:3a22/64 scope link 
       valid_lft forever preferred_lft forever
72: tp-a86608e02f4d: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel master br-ae6a881b3195 state UNKNOWN group default qlen 1000
    link/ether da:fe:f4:7e:f2:68 brd ff:ff:ff:ff:ff:ff
    inet6 fe80::d8fe:f4ff:fe7e:f268/64 scope link 
       valid_lft forever preferred_lft forever
73: br-ae6a881b3195: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether be:01:62:dc:9c:fb brd ff:ff:ff:ff:ff:ff
    inet6 fda5:d6a8:799f:4b5e:bc01:62ff:fedc:9cfb/64 scope global dynamic mngtmpaddr 
       valid_lft 1710sec preferred_lft 243sec
    inet6 2600:1700:760:2120:bc01:62ff:fedc:9cfb/64 scope global dynamic mngtmpaddr 
       valid_lft 3509sec preferred_lft 3509sec
    inet6 fe80::bc01:62ff:fedc:9cfb/64 scope link 
       valid_lft forever preferred_lft forever
74: tp-09b31f56d003: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel master br-e241b85f9d32 state UNKNOWN group default qlen 1000
    link/ether 06:ea:32:bd:f0:1e brd ff:ff:ff:ff:ff:ff
    inet6 fe80::4ea:32ff:febd:f01e/64 scope link 
       valid_lft forever preferred_lft forever
75: br-e241b85f9d32: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 86:59:c2:9f:d9:af brd ff:ff:ff:ff:ff:ff
    inet 10.1.10.1/24 scope global br-e241b85f9d32
       valid_lft forever preferred_lft forever
    inet6 fe80::8459:c2ff:fe9f:d9af/64 scope link 
       valid_lft forever preferred_lft forever

(I've tried this way more than 75 times)

I can ssh into tp-a86608e02f4d using the ipv6 reported by my physical router, and the ip tables in there look like this:

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: tp-a86608e02f4d: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether de:ad:be:ef:68:f9 brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.171/24 brd 192.168.1.255 scope global dynamic noprefixroute tp-a86608e02f4d
       valid_lft 85754sec preferred_lft 74954sec
    inet6 2600:1700:760:2120::38/128 scope global dynamic noprefixroute 
       valid_lft 2951sec preferred_lft 2951sec
    inet6 fda5:d6a8:799f:4b5e:bedf:47d7:fd86:f4d/64 scope global dynamic mngtmpaddr noprefixroute 
       valid_lft 1482sec preferred_lft 197sec
    inet6 2600:1700:760:2120:c2af:9fdd:7a17:eba2/64 scope global dynamic mngtmpaddr noprefixroute 
       valid_lft 3283sec preferred_lft 3283sec
    inet6 fe80::ffd6:85a7:8a5e:184/64 scope link 
       valid_lft forever preferred_lft forever
3: tp-09b31f56d003: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether de:ad:be:ef:73:2d brd ff:ff:ff:ff:ff:ff
    inet6 fe80::45a1:2190:479d:e3fb/64 scope link 
       valid_lft forever preferred_lft forever

checking the status of iptables, systemd-networkd, and dnsmasq there are no warnings or errors save for dnsmasq finding no hosts in resolv.conf; however, if I connect another virtual machine to the bridge with tp-09b, dnsmasq starts throwing errors:

● dnsmasq.service - dnsmasq - A lightweight DHCP and caching DNS server
     Loaded: loaded (/usr/lib/systemd/system/dnsmasq.service; enabled; vendor preset: disabled)
     Active: active (running) since Sat 2022-03-05 16:17:00 UTC; 2min 38s ago
       Docs: man:dnsmasq(8)
    Process: 235 ExecStartPre=/usr/bin/dnsmasq --test (code=exited, status=0/SUCCESS)
   Main PID: 240 (dnsmasq)
      Tasks: 1 (limit: 2360)
     Memory: 3.7M
        CPU: 33ms
     CGroup: /system.slice/dnsmasq.service
             └─240 /usr/bin/dnsmasq -k --enable-dbus --user=dnsmasq --pid-file

Mar 05 16:17:01 installation-63086aae8735 dnsmasq[240]: no servers found in /etc/resolv.conf, will retry
Mar 05 16:17:05 installation-63086aae8735 dnsmasq[240]: reading /etc/resolv.conf
Mar 05 16:17:05 installation-63086aae8735 dnsmasq[240]: using nameserver 2600:1700:760:2120::1#53
Mar 05 16:17:06 installation-63086aae8735 dnsmasq[240]: reading /etc/resolv.conf
Mar 05 16:17:06 installation-63086aae8735 dnsmasq[240]: using nameserver 2600:1700:760:2120::1#53
Mar 05 16:17:08 installation-63086aae8735 dnsmasq[240]: reading /etc/resolv.conf
Mar 05 16:17:08 installation-63086aae8735 dnsmasq[240]: using nameserver 192.168.1.254#53
Mar 05 16:17:08 installation-63086aae8735 dnsmasq[240]: using nameserver 2600:1700:760:2120::1#53
Mar 05 16:19:35 installation-63086aae8735 dnsmasq-dhcp[240]: DHCP packet received on tp-09b31f56d003 which has no address
Mar 05 16:19:39 installation-63086aae8735 dnsmasq-dhcp[240]: DHCP packet received on tp-09b31f56d003 which has no address

Last edited by eom.dev (2022-03-05 16:20:12)

eom.dev · 2022-03-05 18:22:04

Ok, so my systemd-networkd files were still incorrect. The naming and IP assignment does need to occur in different files, but they need different extensions. I was naming both .link when the IP assignment should have been in a .network file.

Currently, dnsmasq is saying:

 no address range available for DHCP request via tp-09b31f56d003

and vultures have begun to circle.

eom.dev · 2022-03-05 18:27:03

And by changing the IP addresses in those network files to fall within the subnet specified in the dnsmasq configuration, it is finally assigning IP addresses to itself, the second host interface, and new guest machines.

Last edited by eom.dev (2022-03-05 19:00:22)

Arch Linux

#1 2022-03-02 22:00:42

[SOLVED] qemu virtual router

#2 2022-03-04 14:00:04

Re: [SOLVED] qemu virtual router

#3 2022-03-04 15:53:47

Re: [SOLVED] qemu virtual router

#4 2022-03-04 16:14:18

Re: [SOLVED] qemu virtual router

#5 2022-03-04 16:26:35

Re: [SOLVED] qemu virtual router

#6 2022-03-04 23:27:23

Re: [SOLVED] qemu virtual router

#7 2022-03-05 01:10:45

Re: [SOLVED] qemu virtual router

#8 2022-03-05 03:00:01

Re: [SOLVED] qemu virtual router

#9 2022-03-05 14:28:52

Re: [SOLVED] qemu virtual router

#10 2022-03-05 16:14:09

Re: [SOLVED] qemu virtual router

#11 2022-03-05 18:22:04

Re: [SOLVED] qemu virtual router

#12 2022-03-05 18:27:03

Re: [SOLVED] qemu virtual router

Board footer