Beberapa minggu ini, salah satu DNS server sering hang. Service server yang berjalan menunjukkan, terdapat layanan email yang berjalan looping dan tidak wajar.
Pada /var/log/mail.log terdapat report seperti:
Sep 8 11:10:07 ns1 postfix/sendmail[1936]: fatal: www-data(33): unable to execute /usr/sbin/postdrop -r: Permission Denied
Sep 8 11:10:07 ns1 postfix/sendmail[1942]: fatal: www-data(33): unable to execute /usr/sbin/postdrop -r: Permission Denied
Sep 8 11:10:07 ns1 postfix/sendmail[1971]: fatal: www-data(33): unable to execute /usr/sbin/postdrop -r: Permission Denied
Sep 8 11:25:51 ns1 postfix/sendmail[2000]: fatal: www-data(33): unable to execute /usr/sbin/postdrop -r: Permission Denied
Sep 8 11:25:51 ns1 postfix/sendmail[1994]: fatal: www-data(33): unable to execute /usr/sbin/postdrop -r: Permission Denied
Sep 8 11:25:51 ns1 postfix/sendmail[1985]: fatal: www-data(33): unable to execute /usr/sbin/postdrop -r: Permission Denied
Sep 8 11:37:46 ns1 postfix/sendmail[2010]: fatal: www-data(33): unable to execute /usr/sbin/postdrop -r: Permission Denied
Sep 8 11:37:46 ns1 postfix/sendmail[2016]: fatal: www-data(33): unable to execute /usr/sbin/postdrop -r: Permission Denied
Untuk membuang pesan ini, dapat dilakukan dengan cara:
root@ns1:/var/spool/postfix# postfix check
postfix/postfix-script: warning: not owned by group postdrop: /var/spool/postfix/public
postfix/postfix-script: warning: not owned by group postdrop: /var/spool/postfix/maildrop
Dan.. solusi agar tidak hang lagi, kita dapat melakukan:
root@ns1:/var/spool/postfix# /etc/init.d/postfix stop
root@ns1:/var/spool/postfix# killall -9 postdrop
root@ns1:/var/spool/postfix# chgrp -R postdrop /var/spool/postfix/public
root@ns1:/var/spool/postfix# chgrp -R postdrop /var/spool/postfix/maildrop/
root@ns1:/var/spool/postfix# postfix check
root@ns1:/var/spool/postfix# postfix reload