---
title: CUPS "Unable to locate printer *.local" even though avahi-resolve finds the printer
date: 2026-05-16
summary: CUPS jobs to an ipp://printer.local queue never printed and lpstat showed "Unable to locate printer". Avahi could see the printer, but /etc/nsswitch.conf had no mdns entry, so normal name lookups for .local failed. Adding mdns4_minimal [NOTFOUND=return] to the hosts line fixed it.
tags: cups, printers, mdns, avahi, nss-mdns, arch
environment: Arch Linux; CUPS with an ipp:// queue addressed by the printer's mDNS (.local) name; avahi-daemon; nss-mdns installed
author: shaun, written up with Claude
status: published
---

## Symptoms

A network printer had been set up in CUPS using its mDNS hostname. The queue accepted jobs,
but nothing printed and jobs piled up. `lpstat -t` showed:

```text
device for Office_Printer: ipp://printer.local:631/ipp/print
Unable to locate printer "printer.local".
```

At the same time, Avahi had no trouble finding the printer:

```bash
avahi-resolve -n printer.local     # returns the printer's address
```

But ordinary name resolution did not:

```bash
getent hosts printer.local         # prints nothing
ping printer.local                 # Name or service not known
```

## Root cause

CUPS resolves the queue's hostname through the normal glibc resolver (NSS), not by asking
Avahi directly. Whether NSS knows about `.local` names is decided by the `hosts:` line in
`/etc/nsswitch.conf`, which here was:

```text
hosts: files dns myhostname
```

There is no `mdns` module in that list, so `.local` lookups went to `files` and `dns`, both
of which fail. The `nss-mdns` package (which provides the `mdns*` NSS modules) was already installed; it
just was not enabled in `nsswitch.conf`. On Arch it is only an *optional* dependency of
avahi, so on another machine you may need `pacman -S nss-mdns` first.

The difference between `avahi-resolve` (works) and `getent hosts` (fails) is the tell:
`avahi-resolve` talks to avahi-daemon directly, `getent` goes through NSS the way CUPS does.

## Fix

Add `mdns4_minimal [NOTFOUND=return]` to the `hosts:` line, before `dns`:

```bash
sudo sed -i.bak 's|^hosts:.*|hosts: files mdns4_minimal [NOTFOUND=return] dns myhostname|' /etc/nsswitch.conf
```

If your `hosts:` line has other entries (for example `resolve` or `mymachines`), edit it by
hand instead of replacing the whole line; the point is to insert
`mdns4_minimal [NOTFOUND=return]` before `dns`.

Check:

```bash
getent hosts printer.local         # now prints the printer's address
```

No service restart is needed: NSS reads `nsswitch.conf` on each lookup, and CUPS picked up
the change on the next job.

`[NOTFOUND=return]` stops the lookup when mDNS says a `.local` name does not exist, instead
of falling through to DNS. That avoids slow upstream DNS queries for names that will never
resolve there.

The same fix applies to any `.local` device on the machine (AirPlay receivers, other
Bonjour/mDNS hosts), not only printers.

### Do not cancel the stuck jobs

Jobs stuck on a name-resolution failure are real prints. Once the hostname resolves, CUPS
retries them and they print. If you cancel them while diagnosing (`cancel -a`), they have
to be printed again. We made this mistake once; leave the queue alone and let it flush.

## How it was found

```bash
lpstat -t                          # queues and the last error per queue
avahi-resolve -n printer.local     # what Avahi sees
getent hosts printer.local         # what NSS (and CUPS) sees: the gap
avahi-browse -art                  # list mDNS services on the network
grep ^hosts /etc/nsswitch.conf     # look for mdns4_minimal
pacman -Q nss-mdns                 # confirm the NSS module is installed
```

## References

- Arch Wiki, [Avahi: Hostname resolution](https://wiki.archlinux.org/title/Avahi#Hostname_resolution).