# WHATPORT(7100)

## NAME

port 7100 — X Font Service (xfs) — The X font server — a legacy daemon that hands rasterized fonts to X11 clients over the network.

Protocol: TCP/UDP  
IANA registry

## DESCRIPTION

IANA registers 7100 as font-service, and the xfs man page confirms the daemon's default port number is 7100. In the X11 model an X server or client with `FontPath` set to `tcp/host:7100` fetches font metrics and glyphs from xfs rather than from local files. Modern desktops render fonts client-side through fontconfig and Xft, so xfs is effectively obsolete; distributions that still ship it default to a local socket or `-nolisten tcp`. An open 7100 today is either a very old X installation or an unrelated application on the number.

## EXPOSURE

**Do not expose.** xfs has no meaningful authentication and is unmaintained legacy code with a history of remote overflow bugs; there is no reason to have it reachable off the host.

## CHECK

```sh
fslsfonts -server TARGET:7100
```

## SEE ALSO

- docs — [xfs(1) — X font server manual page (default port 7100)](https://xorg.freedesktop.org/archive/X11R7.5/doc/man/man1/xfs.1.html) (xorg.freedesktop.org)
- iana — [IANA Service Name and Transport Protocol Port Number Registry — 7100](https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml?search=7100) (iana.org)

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HTML: <https://whatport.net/7100/> · JSON: <https://whatport.net/7100.json> · full dataset: <https://whatport.net/ports.json>