Arch Linux

smelt_

Member

Registered: 2015-07-29

Posts: 4

'connect: Network is unreachable' during Arch installation

Hello,

Yesterday I decided to give the Arch Linux distribution a try and successfully set up a USB flash installation medium with dd using the official guide . I booted into it and did some playing around for a while until I noticed I did not have an internet connection:

# ping -c 3 www.google.com
connect: Network is unreachable
# ping -c 3 8.8.8.8
connect: Network is unreachable

I have been trying to fix this since. I have found several posts addressing similar problems but none of the solutions could fix mine.

Here is the output of ip link:

# ip link
1: lo: <LOOPBACK,UP,LOWER_UP> ...
2: enp2s0: <BROADCAST,MULTICAST,UP,LOWER_UP> ...

What I find strange here is that I have found multiple forum posts suggesting that the archiso setup still uses the interface names prior to the renaming with systemd 197, meaning enp2s0 should actually be be eth0 ... or does that not apply here in some way?
Prior to the installation attempt I had been running Kubuntu on this machine and it most certainly had a connection to the internet.
I have tried dhcpcd with

 # systemctl start dhcpcd@enp2s0.service 

yet nothing has changed.

Sorry if there is something obvious I'm missing or I'm doing something completely wrong ... This is my first encounter with Arch after using Kubuntu for a long time. Be gentle

Last edited by smelt_ (2015-07-29 16:33:07)

ewaller

Administrator

From: Pasadena, CA

Registered: 2009-07-13

Posts: 19,804

Re: 'connect: Network is unreachable' during Arch installation

Does the command dhcpcd do anything interesting?  What is the output of ip addr
Does your computer's NIC have link status LEDs? Are they lit? And Blinking?
Are you plugged into to router or switch that has link LEDs? Are they lit and blinking for the port into which you are plugged?

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Nothing is too wonderful to be true, if it be consistent with the laws of nature -- Michael Faraday
Sometimes it is the people no one can imagine anything of who do the things no one can imagine. -- Alan Turing
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smelt_

Member

Registered: 2015-07-29

Posts: 4

Re: 'connect: Network is unreachable' during Arch installation

Just did a reboot.  # ip link still delivers the same output.

@ewaller

# dhcpcd
DUID ...
enp2s0: IAID ...
enp2s0: soliciting an IPv6 router
enp2s0: Router Advertisement from ...
enp2s0: adding address ...
enp2s0: adding route to ...
forked to backgound, child pid 683
# ip addr
1: lo ...
2: enp2s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
      link/ether ...
      inet6 ... scope global noprefixroute dynamic
          valid_lft 6820sec preferred_lft 3220sec
      inet6 ... scope link
          valid_lft forever preferred_lft forever

Both my NIC port and the switch into which I'm plugged in have blinking status LEDs. I'm actually typing on a second machine connected to the same switch.

EDIT: Call me crazy, but just as I rebooted the status LEDs on my NIC stopped doing anything. Needs investigating.
EDIT 2: Same goes for the LEDs on the switch. The port the machine I'm currently using is plugged into still connects.

Last edited by smelt_ (2015-07-29 17:04:01)

ewaller

Administrator

From: Pasadena, CA

Registered: 2009-07-13

Posts: 19,804

Re: 'connect: Network is unreachable' during Arch installation

Check your cable.

Also, what is the NIC card?  Check using lspci -nn

Curious... dhcpcd did not look for an IPv4 router.      Is your router IPv6 only?  Does the machine from which you are posting have an IPv4 address assigned by the router?

---

Nothing is too wonderful to be true, if it be consistent with the laws of nature -- Michael Faraday
Sometimes it is the people no one can imagine anything of who do the things no one can imagine. -- Alan Turing
---
How to Ask Questions the Smart Way

smelt_

Member

Registered: 2015-07-29

Posts: 4

Re: 'connect: Network is unreachable' during Arch installation

Well that was strange. Just switched around cables repeatedly and the machines sometimes had internet, sometimes did not, yet it did not seem to depend on the cable or the port I plugged them into. Now it's all up and blinking again. I'll have to look into that. During the entire time the Arch machine couldn't connect to the network, though, so I hope we can safely assume it's not connected to that.

What I assume to be the NIC in the output of lspci -nn has the following text:

Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller [10ec:9169] (rev06)

As for the rest, perhaps this is related?

smelt_

Member

Registered: 2015-07-29

Posts: 4

Re: 'connect: Network is unreachable' during Arch installation

Interestingly, after I set up a second USB installation medium and tried the same thing, it worked like a charm, i.e. I had a perfectly fine Internet connection ... at least after I booted into the new system. I followed the Beginner's Guide very closely, all I did additionally is set up a user account with useradd and give him access to sudo. Yet, as I said, when I booted into the newly installed system, I had the exact same problem. All the commands from the above posts deliver pretty much the same output.
The Beginner's Guide does have this interesting hint in #Establish an internet connection:

Tip: The system you are going to install in this guide makes no pre-assumptions regarding network access. For an easy start after the first boot, it may be helpful to stick to the method that got you connected with the live medium and copy relevant configuration to the new system before you #Chroot and configure the base system later.

Sadly, it does not say what the 'relevant configuration' is. I realise this may be a new question altogether, but I do believe it still belongs here as it may solve the problem described in the original post. Perhaps somebody could point me into the right direction?

EDIT: Sorry for double post.

Last edited by smelt_ (2015-07-30 10:24:15)