Postgresql Cron errors

[Aegil]

Hey,

Been getting the following error on my plesk server. I haven't really used postgres myself so I'm not sure how to troubleshoot it. running it manually from root its asking for the password.

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Cron <root@server> if [ -x /usr/sbin/pg_maintenance ]; then
/usr/sbin/pg_maintenance --analyze >/dev/null; fi
Password:
vacuumdb: could not connect to database postgres: fe_sendauth: no
password supplied
calling vacuumdb on cluster 8.3/main failed
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