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merged 3 commits into from
Nov 2, 2025
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pkg/cidata: Enable mDNS in guest using systemd #4272

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4584ef8
pkg/driver/vz: Enable mDNS in guest using `systemd` on macOS host
norio-nomura Nov 1, 2025
ab0d64c
06-enable-mdns-on-systemd.sh: Add checking `systemd-resolved.service`…
norio-nomura Nov 1, 2025
a59ced4
Move `06-enable-mdns-on-systemd.sh` from `pkg/driver/vz` to `pkg/cidata`
norio-nomura Nov 2, 2025
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36 changes: 36 additions & 0 deletions pkg/cidata/cidata.TEMPLATE.d/boot/06-enable-mdns-on-systemd.sh
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@AkihiroSuda AkihiroSuda Nov 1, 2025

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

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@norio-nomura norio-nomura Nov 1, 2025

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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

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@AkihiroSuda AkihiroSuda Nov 1, 2025

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

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@norio-nomura norio-nomura Nov 1, 2025

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

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@norio-nomura norio-nomura Nov 1, 2025

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I'll test with other drivers on macOS.

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@norio-nomura norio-nomura Nov 1, 2025

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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?

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@AkihiroSuda AkihiroSuda Nov 1, 2025

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

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@norio-nomura norio-nomura Nov 1, 2025

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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.

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@norio-nomura norio-nomura Nov 2, 2025

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

Original file line number Diff line number Diff line change
@@ -0,0 +1,36 @@
#!/bin/bash

# SPDX-FileCopyrightText: Copyright The Lima Authors
# SPDX-License-Identifier: Apache-2.0

set -eux -o pipefail

# Do nothing on OpenRC systems (e.g., Alpine Linux)
if [[ -f /sbin/openrc-run ]]; then
exit 0
fi

# It depends on systemd-resolved
command -v systemctl >/dev/null 2>&1 || exit 0
command -v resolvectl >/dev/null 2>&1 || exit 0

# Configure systemd-resolved to enable mDNS resolution globally
enable_mdns_conf_path=/etc/systemd/resolved.conf.d/00-lima-enable-mdns.conf
enable_mdns_conf_content="[Resolve]
MulticastDNS=yes
"
# Create /etc/systemd/resolved.conf.d/00-lima-enable-mdns.conf if its content is different
if ! diff -q <(echo "${enable_mdns_conf_content}") "${enable_mdns_conf_path}" >/dev/null 2>&1; then
mkdir -p "$(dirname "${enable_mdns_conf_path}")"
echo "${enable_mdns_conf_content}" >"${enable_mdns_conf_path}"
systemctl daemon-reload
systemctl restart systemd-resolved.service
fi

# On Ubuntu, systemd.network's configuration won't work.
# See: https://unix.stackexchange.com/a/652582
# So we need to enable mDNS per-link using resolvectl.
for iface in $(resolvectl status | sed -n -E 's/^Link +[0-9]+ \(([^)]+)\)/\1/p'); do
# This setting is volatile and will be lost on reboot, so we need to set it every time
resolvectl mdns "${iface}" yes
done