can't ssh between 2 arch machines over LAN

sfabius · 2012-07-10 22:14:55

I have two arch machines wirelessly connected to a router (Buffalo Airstation). I have set up sshd on machine A and am trying to ssh in from machine B. I can ping both machines from the other. I get a 'connection timed out error' and cannot connect. I followed some of the ssh troubleshooting tips on the wiki, and when I use tcpdump on machine A and get no traffic, even when I ping (and on B I get no packet loss). I am now totally flummoxed and would appreciate help.

Gcool · 2012-07-11 08:19:53

Could you briefly describe your network setup (involved ip's,...) and post the output of "ssh -v <machineA>"?

Also, are you able to ssh locally on machineB (ssh -v localhost)?

ebal · 2012-07-11 08:45:49

Machine A:

test that sshd is started :

 ps -ef | grep ss[h]d

test that the tcp port is open:

 netstat -ntlp | grep sshd

test that your iptables are down or properly setup:

 iptables -F (flush iptables)

try to ssh localhost:

 ssh -v localhost

msx · 2012-07-11 09:00:14

I wonder if you have any firewall enable by chance...

Last edited by msx (2012-07-11 12:00:43)

sfabius · 2012-07-11 10:57:28

Thanks everyone. No firewall, no iptables. I can ssh into localhost.
Results of netstat:

[root]# netstat -ntlp | grep sshd
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      1154/sshd           
tcp6       0      0 :::22                   :::*                    LISTEN      1154/sshd

I'm thinking it might be something to do with the router or machine B. I have B connected to wireless and it has an ipaddress but I can't get out to the internet.

ebal · 2012-07-11 11:18:52

Thats two different problems.

a. ssh connection on local vlan (ethernet network)

If you are trying via the local address (eg. 192.168.x.x) then you should have any problem.
The router doesnt act as a gateway on ethernet.

b. access to internet
In this case the router act as a gateway.
Check the dns resolving and routing table on machive B

sfabius · 2012-07-11 11:51:31

OK, then the router is not the problem (although both machines are going through wireless connections). At this point I just want to ssh between these two machines.

ebal · 2012-07-11 11:53:36

Its time for :

ip a 
ip r

on both machines

sfabius · 2012-07-11 12:06:46

Machine B:

[root]# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN qlen 1000
    link/ether 00:1c:7e:28:8c:ae brd ff:ff:ff:ff:ff:ff
3: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 1000
    link/ether 00:21:5c:18:0e:cb brd ff:ff:ff:ff:ff:ff
    inet 192.168.11.13/24 brd 192.168.11.255 scope global wlan0
    inet6 fe80::221:5cff:fe18:ecb/64 scope link 
       valid_lft forever preferred_lft forever
[root]# ip r
default via 192.168.11.1 dev wlan0  metric 303 
192.168.11.0/24 dev wlan0  proto kernel  scope link  src 192.168.11.13  metric 303

Machine A (eth1 is wireless interface):

[root]#ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: irda0: <NOARP> mtu 2048 qdisc noop state DOWN qlen 8
    link/irda 00:00:00:00 brd ff:ff:ff:ff
3: eth0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN qlen 1000
    link/ether 00:0d:60:d0:20:ed brd ff:ff:ff:ff:ff:ff
4: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 00:0e:35:7b:2c:60 brd ff:ff:ff:ff:ff:ff
    inet 192.168.11.9/24 brd 192.168.11.255 scope global eth1
    inet6 fe80::20e:35ff:fe7b:2c60/64 scope link 
       valid_lft forever preferred_lft forever
[root]# ip r
default via 192.168.11.1 dev eth1  metric 304 
192.168.11.0/24 dev eth1  proto kernel  scope link  src 192.168.11.9  metric 304

Arch Linux

#1 2012-07-10 22:14:55

can't ssh between 2 arch machines over LAN

#2 2012-07-11 08:19:53

Re: can't ssh between 2 arch machines over LAN

#3 2012-07-11 08:45:49

Re: can't ssh between 2 arch machines over LAN

#4 2012-07-11 09:00:14

Re: can't ssh between 2 arch machines over LAN

#5 2012-07-11 10:57:28

Re: can't ssh between 2 arch machines over LAN

#6 2012-07-11 11:18:52

Re: can't ssh between 2 arch machines over LAN

#7 2012-07-11 11:51:31

Re: can't ssh between 2 arch machines over LAN

#8 2012-07-11 11:53:36

Re: can't ssh between 2 arch machines over LAN

#9 2012-07-11 12:06:46

Re: can't ssh between 2 arch machines over LAN

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