<application>pg_checksums</application> checks, enables or disables data

checksums in a <productname>PostgreSQL</productname> cluster. The server

must be shut down cleanly before running

<application>pg_checksums</application>.The exit status is zero if there

are no checksum errors when checking them, and nonzero if at least one

checksum failure is detected.If enabling or disabling checksums, the

<application>pg_checksums</application>.When verifying checksums, the exit

status is zero if thereare no checksum errors, and nonzero if at least one

checksum failure is detected.When enabling or disabling checksums, the

exit status is nonzero if the operation failed.

</para>

<para>

While checking or enablingchecksums needs to scan or write every file in

<filename>pg_control</filename>.

When verifyingchecksums, every file in the cluster is scanned. When

checksums only updates the file<filename>pg_control</filename>.

</para>

</refsect1>

</para>

<para>

If <application>pg_checksums</application> is aborted or killed while

enabling or disabling checksums, the cluster will keep the same

configuration for data checksums as before the operation attempted.

<application>pg_checksums</application> can be restarted to

attempt again the same operation.

enabling or disabling checksums, the cluster's data checksum configuration

remains unchanged, and <application>pg_checksums</application> can be

re-run to perform the same operation.

</para>

</refsect1>

</refentry>