Directories for Unix-domain socket files.
At a glance
| Property | Value |
|---|---|
| Parameter | unix_socket_directories |
| Category | Connections |
| Default | '/tmp' |
| Value type | boolean / enum / numeric |
| Change scope | Restart required |
What it does
Lists the directories in which the server creates Unix-domain sockets. Many packaged builds default to /var/run/postgresql.
How to apply a change
Requires a full server restart (postmaster context). Set it in postgresql.conf and restart PostgreSQL.
Inspect the current value and source with SHOW unix_socket_directories; or SELECT name, setting, unit, context, source FROM pg_settings WHERE name = 'unix_socket_directories';.
Tuning guidance
Match this to where your clients and libpq look (PGHOST). Mismatches cause “could not connect to server: No such file or directory” on local connections.