Virtual TapeServer 8.3 Configuration Guide

168 | Virtual TapeServer Configuration Guide
ps –xaf — Lists running processes
tail –f –n 24 filename — Displays a real-time file listing
grep filename — Searches for a string in a file
man — Displays help for a program
more filename — Lists a file
reset — Resets the current terminal
Following a hard (unclean) shutdown of VTS (such as a system crash or loss of power), the system
may be left in an inconsistent state. Many services running on the server use PID files to tell the
system that a service is running. When a service is started, the PID file is created. When a service is
shutdown, the PID file is deleted. If VTS is shutdown uncleanly, the PID files will not be deleted. When
the system comes back up, it assumes that the service is running and does not try to restart the
service. This will cause VTS to function incorrectly or not at all. Here is an example of a service
failing to start due to a stale PID file that resulted from a crashed server, in /var/log/messages.
Nov 6 12:29:18 ProdVTS rhdb: Starting PostgreSQL - Red Hat Edition service:
failed
To address this issue, reboot the server twice. This will allow the server to clean up the PID files as
the server shuts down and allows all of the necessary services to start properly when the server
boots up.
Web interface
If the web interface stops responding, verify the following:
l Access the interface from a different workstation.
l Ping the address.
l Check the Ethernet cable.
l Check Ethernet connectivity and activity LEDs.
The Apache web server is responsible for running the VTS web interface. To verify that Apache is
running:
/etc/init.d/httpd status
A message similar to the following should be displayed:
httpd (pid 25380 25015 25014 25013 25012 25011) is running...
You can reboot VTS to attempt to solve the problem.
SCSI converter
During normal operation, the LEDs on the SCSI converter blink every 3-5 seconds. During backups,
the activity LED is almost solidly lit.
l Is the power turned on?
l Are all of the cables secured tightly?