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#1 2017-03-22 03:29:07
- audiomuze
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Lost ssh access after running update using pacman [resolved]
My headless server has been running Arch for over a year without any issues and ssh has also worked without issue during this time. Yesterday I ran an arch update which ran successfully, however, after rebooting to take account of kernel updates I could no longer access the server via ssh - not as a regular user nor as root (which is previously explicitly re-enabled quite some time back). I know it's rebooted successfully as the server application it runs is accessible by its clients on the network and I can NFS mount the server drives.
Before I dig out a monitor and keyboard, have there been any recent changes to Arch that would trigger this?
Last edited by audiomuze (2017-03-22 08:20:16)
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#2 2017-03-22 03:49:52
- jasonwryan
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Re: Lost ssh access after running update using pacman [resolved]
Read the pacman log and the journal entries for the ssh service.
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#3 2017-03-22 04:03:55
- audiomuze
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Re: Lost ssh access after running update using pacman [resolved]
How? I don't have access to the server OS. I guess I could pull the flash drive it boots from and pop it in my Arch desktop machine.
Last edited by audiomuze (2017-03-22 04:08:09)
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#4 2017-03-22 04:22:30
- jasonwryan
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Re: Lost ssh access after running update using pacman [resolved]
You said in your first post you could pull out a monitor and keyboard...
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#5 2017-03-22 07:58:24
- audiomuze
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Re: Lost ssh access after running update using pacman [resolved]
Unfortunately my logs on that box aren't persistent as they're written to tmpfs. Anyhow, the problem seems to me to be upstream with sshd.service or a change to /etc/ssh/sshd_config. systemctl status sshd.service returns:
sshd.service - OpenSSH Daemon
Loaded: loaded (/usr/lib/systemd/sshd.service; enabled; vendor preset: disabled)
Active: failed (Result: exit-code) since Wed 2017-03-22 08:44:57 SAST; 20min ago
Process: 681 ExecStart=/usr/bin/sshd- D (code=exited, status=255)
Main PID: 681 (code=exited, status=255)Tried reinstalling it and got same outcome.
Looked at timestamp of /etc/ssh/sshd_config and I see it was changed last night ... so I'm guessing some config was modified by the update and went awry.
Damnit, chasing the rabbithole.
Last edited by audiomuze (2017-03-22 08:04:09)
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#6 2017-03-22 08:03:46
- audiomuze
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Re: Lost ssh access after running update using pacman [resolved]
Yip, reverted to an earlier sshd_config and all's good again. Should I be reporting a bug ?
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#7 2017-03-22 08:17:19
- jasonwryan
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Re: Lost ssh access after running update using pacman [resolved]
No. The update shouldn't have touched your config, it should have created a .pacnew that you can compare with your current config.
What is the diff between the two configs?
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#8 2017-03-22 08:19:22
- audiomuze
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Re: Lost ssh access after running update using pacman [resolved]
These are the changes made by the update:
--- sshd_config.bk
+++ sshd_config
@@ -97,12 +97,11 @@
UsePAM yes
#AllowAgentForwarding yes
-AllowTcpForwarding yes
+#AllowTcpForwarding yes
#GatewayPorts no
X11Forwarding yes
-X11DisplayOffset 10
-X11UseLocalhost yes
-ForwardX11Trusted yes
+#X11DisplayOffset 10
+#X11UseLocalhost yes
#PermitTTY yes
PrintMotd no # pam does that
#PrintLastLog yes
Last edited by audiomuze (2017-03-22 08:20:39)
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#9 2017-03-22 08:29:47
- jasonwryan
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Re: Lost ssh access after running update using pacman [resolved]
You should work out why your config was overwritten, rather than pacnew'ed. I also don't see any change that would lock you out...
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#10 2017-03-22 10:17:23
- audiomuze
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Re: Lost ssh access after running update using pacman [resolved]
I learned something today. I see there is a pacnew. It might've been me that made the x11 related changes as I've been using x-forwarding of late. Still, nor sure why the server speed working with those changes... Guess I need to go read some.
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