---
name: "portreserve"
section: "1"
platform: "linux"
package: "portreserve"
version: "0.0.4-1+b2"
release: "Debian 11 (Bullseye)"
platforms: ["linux"]
url: "https://new.carta.tech/portreserve"
---

# portreserve(1)

reserve ports to prevent portmap mapping them

## NAME

portreserve - reserve ports to prevent portmap mapping them

## SYNOPSIS

**portreserve**

## DESCRIPTION

The **portreserve** program aims to help services with well-known ports that lie in the **bindresvport** range. It prevents portmap (or other programs using **bindresvport**) from occupying a real service's port by occupying it itself, until the real service tells it to release the port (generally in its init script).

It is intended that **portreserve** runs from an initscript of its own, and services wishing to interact with it should use **portrelease**.

When the **portreserve** daemon is started, it examines the /etc/portreserve/ directory. Each file not containing “.” or “~” in its name is considered to be a service configuration file, and must contain a service name (as listed in /etc/services) or a port number. UDP services may be specified by appending "/udp" to the service name, and TCP services by "/tcp". Several services may be specified, one per line.

For example, /etc/portreserve/cups might contain the string “ipp” or, equivalently, “ipp/tcp” and “ipp/udp” on separate lines.

For each service configuration file, a socket is created and bound to the appropriate port. A service wishing to bind to its port must first run **portrelease**, which instructs **portreserve** to release the port associated with the service.

Once all the reserved ports have been released, the daemon exits.

## FILES

/etc/portreserve/\*

Service configuration files

/var/run/portreserve/socket

communication socket for **portrelease**

## SEE ALSO

[**portrelease**(1)](/portrelease/1.md)

## AUTHOR

**Tim Waugh** \<twaugh@redhat.com\>

Author.