Files
housecarl/docs/operations.md
T
abrown38andClaude Opus 5.5 2880f7ddc9 Add changesets, bandwidth limits and quotas; generic examples
Changesets, as in Jarl: configuration changes are operations that can be
staged in a changeset, checked as they are added (validation and nft -c),
reviewed with the diff of the ruleset, and applied together as one
history entry, then on probation like any change made over the network.
The web UI collects edits for review by default (pending rows, a bar with
Review and Apply now, a Changes page, a switch for live edits); hc stages
with -C ID or HOUSECARL_CHANGESET (checked like JARL_CHANGESET) and has
hc changeset create/list/show/diff/apply/discard/remove. Undo, import and
takeover refuse a changeset. --dry-run shows the ruleset's diff.

Bandwidth and quotas: rate limits in bytes, per source or destination;
quotas per rule or per address that reset daily, weekly, monthly on a
day, or by hand, with their usage carried across reloads, saved for
reboots, shown by hc quotas and on the rules page, and reset with hc rule
reset-quota. Rules that count traffic are checked before established
connections are accepted (so they see every packet) and can't accept.
Per-address limits group IPv6 by /64 by default (--group-v4/-v6).
Per-source rate meters use update. The importer turns meters, byte rates
and quotas into these fields.

The examples in the web UI, hc's help and the docs use documentation
addresses and generic names instead of the maintainer's network.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
2026-10-19 11:18:54 +01:00

157 lines
5.4 KiB
Markdown

# Running Housecarl
## The services
```sh
systemctl status housecarl # housecarld: the API, the web UI, the log
journalctl -u housecarl -f
systemctl reload housecarl # reread the TLS certificate
systemctl status housecarl-ruleset # the ruleset loaded at boot
```
The firewall itself is the kernel's: it stays in force while housecarld
is stopped, restarted or upgraded. Without housecarld there is no API,
no web UI, no log and no probation timer.
housecarld logs each change it applies, rollbacks, and what it couldn't
apply. When it starts, it applies the configuration again (rolling back
first what was on probation when it stopped).
## Reviewing before applying
In the web UI, edits are collected as pending changes (the bar under the
header), and Changes shows them with the diff of the ruleset; Apply puts
them in force together. The switch in the header (Review edits / Live
edits) applies each edit at once instead. With hc, see
[cli.md](cli.md#changesets).
## Changes on probation
Changes made over the network roll back unless confirmed
([design.md](design.md#not-locking-yourself-out)):
```sh
hc status # Probation: 2 changes roll back in 97s unless confirmed
hc confirm
hc rollback # or undo them now
```
The web UI shows a banner with a countdown and both buttons. A rollback
is in the history, as an undo by `housecarl` via `rollback`, so it can be
undone like any change.
If you are cut off by a change: wait. When the time is up, the previous
ruleset comes back by itself. If you are cut off by a confirmed change,
use the console, or SSH from a source the rules still let in:
```sh
sudo hc history list
sudo hc history undo 42
```
## The ruleset at boot
A confirmed ruleset (or one changed through the socket) is saved to
`/var/lib/housecarl/ruleset.nft`, which `housecarl-ruleset.service`
loads before the network comes up. To see what would load:
```sh
sudo cat /var/lib/housecarl/ruleset.nft
sudo nft -c -f /var/lib/housecarl/ruleset.nft # check it
```
Dynamic sets start empty after a reboot.
Keep Debian's `nftables.service` disabled, or `/etc/nftables.conf`
without `flush ruleset`: otherwise it deletes Housecarl's table at
boot. `housecarl-ruleset.service` runs after it, which covers the
ordinary case.
## Hits
Every rule, NAT rule, built-in and policy has a counter. `hc rule list`,
`hc forward list` and the web UI show packets; `hc counters` shows them
all, with bytes. They count from housecarld's start, and carry across
changes to the ruleset.
## Quotas
`hc quotas` (and the rules page) show what each quota used and when it
resets; `hc rule reset-quota ID` starts one again. housecarld resets
quotas at midnight when their period ends (late, if it was stopped then),
and saves their usage every five minutes and when it stops; after a
reboot it puts it back. A reboot without a clean stop loses at most the
last five minutes' count.
## The log
Rules with `--log` (Log in the web UI) and, with `hc settings set
--log-drops on`, what the input and forward policies drop (at most 10
packets a second) are logged:
```sh
hc log -f
hc log --search 198.51.100.7
```
```
10:02:13 hc input #95 drop: wan - 198.51.100.7:53868 -> 203.0.113.10:22 tcp syn
10:02:15 hc forward policy drop: wan eth1 198.51.100.9:443 -> 192.168.1.20:51432 tcp
```
The packets go to netlink log group 4171, where housecarld reads them;
the last 2000 are kept in memory. They aren't written to the kernel log
or the journal. A rule's log isn't rate-limited: on a busy rule, give it
a limit, or log only new connections (`--state new`).
## When something doesn't get through
1. `hc log -f` with `--log-drops on`: is it dropped by a policy (no rule
accepted it), or by a rule (its number is in the line)?
2. `hc rule list forward` (or `input`): hits on the rule you expect?
3. `hc ruleset`: the rule as nftables sees it, with the zones' interfaces
and the sets' families.
4. `hc status`: other tables. A Docker or Incus table, or an old one,
can drop what Housecarl accepts.
5. Port forwards: `hc forward list` hits, and the inside host's own
firewall and default route (answers must go back through Housecarl).
## Backups
`housecarl-backup.timer` runs `housecarld backup` daily. It writes a
consistent copy of the database to `backup.dir`
(`/var/backups/housecarl/housecarl-<time>.db`), and deletes those older
than `backup.retention` (30 days), keeping at least
`backup.keep_at_least` (7). A backup holds everything: configuration,
history, users, tokens (hashed) and the audit log.
```sh
sudo -u housecarl housecarld backup # now
sudo -u housecarl housecarld backup /tmp/h.db # to a file of your choice
sudo systemctl disable --now housecarl-backup.timer # no daily backups
```
To **restore**, stop housecarld first; restore refuses to replace the
database under it:
```sh
sudo systemctl stop housecarl
sudo -u housecarl housecarld restore /var/backups/housecarl/housecarl-20261014T020000Z.db
sudo systemctl start housecarl
```
housecarld applies the restored configuration when it starts. The old
database is kept next to it as `housecarl.db.before-restore-<time>`.
## Upgrades
`apt upgrade` restarts a running housecarld. A new version upgrades the
database when it starts, and an older one refuses a database a newer one
has upgraded: restore a backup to go back.
## Checks
`housecarld check` validates the configuration in the database against
this machine's interfaces, the same checks as `hc status` shows
([validation.md](validation.md)).