hive-ci is the one container on the hive bridge that used DHCP
(networking.interfaces.eth0.useDHCP = true, from #2310 / #2336). But the
bridge has no DHCP server: dnsmasq on the bridge is DNS-only and agent
containers get deterministic static IPs (lifecycle::agent_network_ip),
so the DHCP client never gets a lease and the container hangs at boot:
A start job is running for DHCP Client (5s / 1min 31s)
Assign a static address on eth0 (top host address of the subnet) plus a
default route via the bridge gateway, and drop useDHCP. Preserves the
#2310 netns isolation (no host-loopback reach) while letting the
container boot and reach the forge through the gateway.
Refs #2310, #2336.
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