Unable to access F5 GUI

Review Logs

TomCat

/var/log/tomcat/catalina.out

HTTPd

/var/log/httpd/httpd_errors

F5 Support Article
https://support.f5.com/csp/article/K13444

Look at services

bigstart status tomcast httpd

Restart Services

[dennis@usmifnt01:/S1-green-P:Standby:In Sync] ~ # bigstart restart tomcat httpd
Stopping httpd: [  OK  ]
Starting httpd: [  OK  ]

Usage: bigstart <action> [service]
        Where <action> is [add|del|disable|enable|erase|kill|list|memstat|pre|reinit|remove|restart|shutdown|singlestatus|start|startup|status|stop]
        And [service] is the name of a service.
        bigstart [startup|shutdown|restart|status]
           Perform the appropriate action on all default services
        bigstart [startup|shutdown|restart|reinit|status|kill] <servicename>..
           Perform the appropriate action on the named services
        bigstart [disable|enable] <servicename>..
           Manually disable and re-enable the named services
        bigstart <add|remove> <servicename>...
           Make the service start/stop on boot.
        bigstart <add|remove> [--default] <servicename>
           Include the service in the default action list.
        bigstart list [<servicename>...]
           Tell when the services will start.
        bigstart memstat [<servicename>...]
           Show memory allocation limit(s).

Another option for restarting

[dennis@usmifnt01:/S1-green-P:Standby:In Sync] ~ # tmsh restart /sys service tomcat

tmsh restart /sys service <service name>