It's not clear how it was changed or where it was changed, but after the upgrade to 6.1.1, the file /etc/mongodb.conf had the following: pidfilepath=/var/run/mongodb/mongod.pid This caused systemd to complain that the pid file was not readable as seen below. [root@satellite6 05-foreman-ssl.d]# systemctl status mongod mongod.service - High-performance, schema-free document-oriented database Loaded: loaded (/usr/lib/systemd/system/mongod.service; enabled) Active: failed (Result: timeout) since Wed 2015-08-12 10:33:25 EDT; 52min ago Process: 31952 ExecStart=/usr/bin/mongod $OPTIONS run (code=exited, status=0/SUCCESS) Main PID: 27029 (code=exited, status=0/SUCCESS) Aug 12 10:31:55 satellite6.rdu.salab.redhat.com mongod[31952]: about to fork child process, waiting until server is ready for connections. Aug 12 10:31:55 satellite6.rdu.salab.redhat.com mongod[31952]: forked process: 31954 Aug 12 10:31:55 satellite6.rdu.salab.redhat.com mongod[31952]: all output going to: /var/lib/mongodb/mongodb.log Aug 12 10:31:57 satellite6.rdu.salab.redhat.com mongod[31952]: child process started successfully, parent exiting Aug 12 10:31:57 satellite6.rdu.salab.redhat.com systemd[1]: PID file /var/run/mongodb/mongodb.pid not readable (yet?) after start. Aug 12 10:33:25 satellite6.rdu.salab.redhat.com systemd[1]: mongod.service operation timed out. Terminating. Aug 12 10:33:25 satellite6.rdu.salab.redhat.com systemd[1]: Failed to start High-performance, schema-free document-oriented database. Aug 12 10:33:25 satellite6.rdu.salab.redhat.com systemd[1]: Unit mongod.service entered failed state. [root@satellite6 05-foreman-ssl.d]# stat /var/run/mongodb/mongod.pid File: ‘/var/run/mongodb/mongod.pid’ Size: 6 Blocks: 8 IO Block: 4096 regular file Device: 12h/18d Inode: 26113409 Links: 1 Access: (0644/-rw-r--r--) Uid: ( 184/ mongodb) Gid: ( 995/ mongodb) Context: system_u:object_r:mongod_var_run_t:s0 Access: 2015-08-12 11:25:41.320144434 -0400 Modify: 2015-08-12 10:31:55.422152480 -0400 Change: 2015-08-12 10:31:55.422152480 -0400 Birth: - Version-Release number of selected component (if applicable): mongodb-server-2.4.9-3.el7sat.x86_64 /etc/mongodb.conf even had mongodb.pid set looking at the rpm. So something during the installer/upgrade changed it.
changing the pidfilepath in /etc/mongodb.conf to pidfilepath=/var/run/mongodb/mongodb.pid Fixed the issue and mongodb starts successfully.
*** This bug has been marked as a duplicate of bug 1248663 ***