fix(cmdeploy): replace resolvconf/systemd-resolved with static resolv.conf, purge

1e376f7 explicitly installed resolvconf to fix DNS breakage after
ff541b8 disabled APT recommends. But resolvconf adds dynamic resolver
management and is unnecessary on a server. Similarly, systemd-resolved
competes for /etc/resolv.conf.

Write a static resolv.conf with unbound as primary and 9.9.9.9 as
fallback. Purge resolvconf, stop and mask systemd-resolved to prevent it
from overriding the static configuration.
This commit is contained in:
j4n
2026-04-20 09:32:29 +02:00
parent 0aa08b7413
commit 825831ee81

View File

@@ -150,18 +150,40 @@ class UnboundDeployer(Deployer):
self.need_restart = False
def install(self):
# Run local DNS resolver `unbound`. `resolvconf` takes care of
# setting up /etc/resolv.conf to use 127.0.0.1 as the resolver.
# On an IPv4-only system, if unbound is started but not configured,
# it causes subsequent steps to fail to resolve hosts.
with blocked_service_startup():
apt.packages(
name="Install unbound",
packages=["unbound", "unbound-anchor", "dnsutils", "resolvconf"],
packages=["unbound", "unbound-anchor", "dnsutils"],
)
def configure(self):
# Remove dynamic resolver managers that compete for /etc/resolv.conf.
apt.packages(
name="Purge resolvconf",
packages=["resolvconf"],
present=False,
extra_uninstall_args="--purge",
)
# systemd-resolved can't be purged due to dependencies; stop and mask.
server.shell(
name="Stop and mask systemd-resolved",
commands=[
"systemctl stop systemd-resolved.service || true",
"systemctl mask systemd-resolved.service",
],
)
# Configure unbound resolver with Quad9 fallback and a trailing newline
# (SolusVM bug).
files.put(
name="Write static resolv.conf",
src=BytesIO(b"nameserver 127.0.0.1\nnameserver 9.9.9.9\n"),
dest="/etc/resolv.conf",
user="root",
group="root",
mode="644",
)
server.shell(
name="Generate root keys for validating DNSSEC",
commands=[
@@ -568,14 +590,6 @@ def deploy_chatmail(config_path: Path, disable_mail: bool, website_only: bool) -
Deployment().perform_stages([WebsiteDeployer(config)])
return
if host.get_fact(Port, port=53) != "unbound":
files.line(
name="Add 9.9.9.9 to resolv.conf",
path="/etc/resolv.conf",
# Guard against resolv.conf missing a trailing newline (SolusVM bug).
line="\nnameserver 9.9.9.9",
)
# Check if mtail_address interface is available (if configured)
if config.mtail_address and config.mtail_address not in ('127.0.0.1', '::1', 'localhost'):
ipv4_addrs = host.get_fact(hardware.Ipv4Addrs)