One of our machines experienced a tailscale agent crash, and then failed to restart with the following error:
systemd-networkd[1182]: tailscale0: Link DOWN
systemd-networkd[1182]: tailscale0: Lost carrier
systemd[1]: tailscaled.service: Main process exited, code=killed, status=4/ILL
tailscaled[1134558]: SIGILL: illegal instruction
tailscaled[1134558]: PC=0x45d530 m=0 sigcode=2
tailscaled[1134558]: instruction bytes: 0xff 0xff 0x48 0x8b 0x54 0x24 0x50 0x48 0x89 0x2 0x48 0x8b 0x6c 0x24 0x58 0x48
tailscaled[1134558]: goroutine 0 [idle
systemd[1]: tailscaled.service: Control process exited, code=dumped, status=4/ILL
systemd[1]: tailscaled.service: Failed with result 'signal'.
systemd[1]: tailscaled.service: Scheduled restart job, restart counter is at 1.
systemd[1]: Stopped Tailscale node agent.
systemd[1]: Starting Tailscale node agent...
tailscaled[1134571]: SIGILL: illegal instruction
tailscaled[1134571]: PC=0x45d530 m=0 sigcode=2
tailscaled[1134571]: instruction bytes: 0xff 0xff 0x48 0x8b 0x54 0x24 0x50 0x48 0x89 0x2 0x48 0x8b 0x6c 0x24 0x58 0x48
tailscaled[1134571]: goroutine 0 [idle
systemd[1]: tailscaled.service: Control process exited, code=dumped, status=4/ILL
tailscaled[1134577]: SIGILL: illegal instruction
tailscaled[1134577]: PC=0x45d530 m=0 sigcode=2
tailscaled[1134577]: instruction bytes: 0xff 0xff 0x48 0x8b 0x54 0x24 0x50 0x48 0x89 0x2 0x48 0x8b 0x6c 0x24 0x58 0x48
tailscaled[1134577]: goroutine 0 [idle
systemd[1]: tailscaled.service: Control process exited, code=dumped, status=4/ILL
systemd[1]: tailscaled.service: Failed with result 'core-dump'.
systemd[1]: Failed to start Tailscale node agent.
systemd[1]: tailscaled.service: Scheduled restart job, restart counter is at 2.
systemd[1]: Stopped Tailscale node agent.
systemd[1]: Starting Tailscale node agent...
tailscaled[1134583]: SIGILL: illegal instruction
tailscaled[1134583]: PC=0x45d530 m=0 sigcode=2
tailscaled[1134583]: instruction bytes: 0xff 0xff 0x48 0x8b 0x54 0x24 0x50 0x48 0x89 0x2 0x48 0x8b 0x6c 0x24 0x58 0x48
tailscaled[1134583]: goroutine 0 [idle
systemd[1]: tailscaled.service: Control process exited, code=dumped, status=4/ILL
tailscaled[1134588]: SIGILL: illegal instruction
tailscaled[1134588]: PC=0x45d530 m=0 sigcode=2
tailscaled[1134588]: instruction bytes: 0xff 0xff 0x48 0x8b 0x54 0x24 0x50 0x48 0x89 0x2 0x48 0x8b 0x6c 0x24 0x58 0x48
tailscaled[1134588]: goroutine 0 [idle
systemd[1]: tailscaled.service: Control process exited, code=dumped, status=4/ILL
systemd[1]: tailscaled.service: Failed with result 'core-dump'.
systemd[1]: Failed to start Tailscale node agent.
systemd[1]: tailscaled.service: Scheduled restart job, restart counter is at 3.
systemd[1]: Stopped Tailscale node agent.
systemd[1]: Starting Tailscale node agent...
tailscaled[1134593]: SIGILL: illegal instruction
tailscaled[1134593]: PC=0x45d530 m=0 sigcode=2
tailscaled[1134593]: instruction bytes: 0xff 0xff 0x48 0x8b 0x54 0x24 0x50 0x48 0x89 0x2 0x48 0x8b 0x6c 0x24 0x58 0x48
tailscaled[1134593]: goroutine 0 [idle
systemd[1]: tailscaled.service: Control process exited, code=dumped, status=4/ILL
tailscaled[1134597]: SIGILL: illegal instruction
tailscaled[1134597]: PC=0x45d530 m=0 sigcode=2
tailscaled[1134597]: instruction bytes: 0xff 0xff 0x48 0x8b 0x54 0x24 0x50 0x48 0x89 0x2 0x48 0x8b 0x6c 0x24 0x58 0x48
I notice there is a core dump in /var/crash but if I attempt to base64 --decode it I get “invalid input”.
I couldn’t find docs on what “status=4/ILL” was in Tailscale, or what illegal instruction it could be. What could cause this failure and why would it fail to restart? My questions were:
- How would I debug this?
- What does “status=4/ILL” mean and what illegal instruction is it failing on? Is it a combination of option I have setup? I use sudo tailscale up --advertise-routs= --exit-node= --exit-node-allow-lan-access.
- Are there any docs that point to this? I couldn’t find any on searching docs: Troubleshooting guide · Tailscale