libnss-myhostname - 247.3-7+deb11u4 main

This package contains a plugin for the Name Service Switch, providing host
name resolution for the locally configured system hostname as returned by
gethostname(2). It returns all locally configured public IP addresses or -- if
none are configured, the IPv4 address 127.0.1.1 (which is on the local
loopback) and the IPv6 address ::1 (which is the local host).
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A lot of software relies on that the local host name is resolvable. This
package provides an alternative to the fragile and error-prone manual editing
of /etc/hosts.
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Installing this package automatically adds myhostname to /etc/nsswitch.conf.