Serial Console in a Zone
In the past, I’ve talked about serial consoles. I have described how to set up a serial console on Solaris/OpenIndiana. I’ve talked about Grub’s composite console in Illumos-based distros. This time, I’m going do describe the one trick necessary to get tip(1) in a zone working.
In my case, I am using SmartOS to run my zones. Sadly, SmartOS doesn’t support device pass-through of this sort, so I have to tweak the zone config after I create the zone with vmadm.
Let’s assume that the serial port I want to pass through is /dev/term/a. Passing it through into a zone is as easy as:
[root@isis ~]# zonecfg -z 7cff99f6-2b01-464d-9f72-d0ef16ce48af zonecfg:7cff99f6-2b01-464d-9f72-d0ef16ce48af> add device zonecfg:7cff99f6-2b01-464d-9f72-d0ef16ce48af:device> set match=/dev/term/a zonecfg:7cff99f6-2b01-464d-9f72-d0ef16ce48af:device> end zonecfg:7cff99f6-2b01-464d-9f72-d0ef16ce48af> commit
At this point, you’ll probably want to reboot the zone (I don’t remember if it is strictly necessary). Once it is back up, you’ll want to get into the zone and point your software of choice at /dev/term/a. It doesn’t matter that you are in a zone. The same configuration rules apply — in my case, it’s the same change to /etc/remote as I described previously.