Container shell with no password

Proxmox VE has an unusual default way to get a shell in an LXC container - the GUI method basically follows the CLI logic of the bespoke pct command: ¹

pct console 100

Connected to tty 1
Type <Ctrl+a q> to exit the console, <Ctrl+a Ctrl+a> to enter Ctrl+a itself

Fedora Linux 39 (Container Image)
Kernel 6.8.12-4-pve on an x86_64 (tty2)

ct1 login: 

But when you think of it, what is going on? These are LXC containers, ² so it’s all running on the host just using kernel containment features. And you are already authenticated when on the host machine.

[!NOTE]

This is a little different in PVE cluster when using shell on another node, then such connection has to be relayed to the actual host first, but let’s leave that case aside here.

So how about reaching out for the native tooling? ³

lxc-info 100

Name:           100
State:          RUNNING
PID:            1344
IP:             10.10.10.100
Link:           veth100i0
 TX bytes:      4.97 KiB
 RX bytes:      93.84 KiB
 Total bytes:   98.81 KiB

Looks like our container is all well, then:

lxc-attach 100

[root@ct1 ~]#

Yes, that’s right, a root shell, of our container:

cat /etc/os-release 

NAME="Fedora Linux"
VERSION="39 (Container Image)"
ID=fedora
VERSION_ID=39
VERSION_CODENAME=""
PLATFORM_ID="platform:f39"
PRETTY_NAME="Fedora Linux 39 (Container Image)"

---8<---

Well, and that’s about it.