pkg/cidata: Enable mDNS in guest using systemd

[norio-nomura]

This change allows resolving <guest's hostname>.local to guest ip by mDNS on macOS host.

e.g.

$ limactl start --name shared-and-vznat --tty=false --network=lima:shared,vzNAT --containerd=none --log-level error
...
$ dns-sd -q lima-shared-and-vznat.local
DATE: ---Sat 01 Nov 2025---
15:31:14.555  ...STARTING...
Timestamp     A/R  Flags         IF  Name                          Type   Class  Rdata
15:31:14.555  Add  40000003      27  lima-shared-and-vznat.local.  Addr   IN     192.168.64.2
15:31:14.555  Add  40000002      31  lima-shared-and-vznat.local.  Addr   IN     192.168.105.3
^C
$ ping -c 1 lima-shared-and-vznat.local
PING lima-shared-and-vznat.local (192.168.64.2): 56 data bytes
64 bytes from 192.168.64.2: icmp_seq=0 ttl=64 time=0.568 ms

--- lima-shared-and-vznat.local ping statistics ---
1 packets transmitted, 1 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 0.568/0.568/0.568/0.000 ms

[AkihiroSuda]

Doesn't this work with other drivers with lima:shared ?

[norio-nomura]

It works.

$ limactl start --name bridged --tty=false --network=lima:bridged --containerd=none --log-level=error
...
$ ping -c 1 lima-bridged.local
PING lima-bridged.local (192.168.12.43): 56 data bytes
64 bytes from 192.168.12.43: icmp_seq=0 ttl=64 time=1.068 ms

--- lima-bridged.local ping statistics ---
1 packets transmitted, 1 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 1.068/1.068/1.068/nan ms
$ limactl start --name host-only --tty=false --network=lima:host --containerd=none --log-level=error
...
$ ping -c 1 lima-host-only.local
PING lima-host-only.local (192.168.106.2): 56 data bytes
64 bytes from 192.168.106.2: icmp_seq=0 ttl=64 time=1.090 ms

--- lima-host-only.local ping statistics ---
1 packets transmitted, 1 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 1.090/1.090/1.090/nan ms

[AkihiroSuda]

Does it work with QEMU, krunkit, and other potential drivers too?

[norio-nomura]

Sorry, PR's title was not correct. Fixed.

[norio-nomura]

I'll test with other drivers on macOS.

[norio-nomura]

It works with qemu and krunkit.

$ ping -c 1 lima-qemu.local
PING lima-qemu.local (192.168.105.6): 56 data bytes
64 bytes from 192.168.105.6: icmp_seq=0 ttl=64 time=0.748 ms

--- lima-qemu.local ping statistics ---
1 packets transmitted, 1 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 0.748/0.748/0.748/0.000 ms
$ ping -c 1 lima-krunkit.local
PING lima-krunkit.local (192.168.105.5): 56 data bytes
64 bytes from 192.168.105.5: icmp_seq=0 ttl=64 time=1.005 ms

--- lima-krunkit.local ping statistics ---
1 packets transmitted, 1 packets received, 0.0% packet loss
round-trip min/avg/max/stddev = 1.005/1.005/1.005/nan ms

Is there already a way to limit the execution of the boot script by the host OS?

[AkihiroSuda]

The script shouldn't care about the host OS. There should be a CIDATA variable that indicates the existence of IP-reachable network.

[norio-nomura]

At first, I tried to enable mDNS on the corresponding interface when Direct IP was detected, not as a boot script.
However, if there is no mDNS environment on the host OS side, I thought it would be meaningless to enable it, so I wanted to limit it to macOS.

[norio-nomura]

Moved 06-enable-mdns-on-systemd.sh from pkg/driver/vz to pkg/cidata.

[AkihiroSuda]

Thanks

[norio-nomura]

Thanks! 🙏🏻