Chapter 9. Troubleshooting

This chapter lists an assortment of common problems and their solutions.

The problems solved include:

625/50 Clips Do Not Play

The default values for the controls are NTSC-specific. If you are using a 625/50 system, set the following system control in /usr/vtr/config/system-defaults/main:

vtr.main.timing_standard 625 

This control sets the timing of the system, including the DIVO cards, to 625/50.

In /usr/vtr/config/device-defaults/DIVO, make sure the control is set to its default value, system.

Adding a Clip Takes Excessively Long

Adding clips always has a lower priority than playout and recording.

DIVO Is Left in Bad State

If you find that the DIVO board has been left in a bad state, for example, you cannot reset it, use the divo_reset command, included in the divo.sw.diag images, to correct the problem. For example, the DIVO reset command is in the directory, /usr/dmedia/DIVO/bin.

If you are using a 625/50 system, see “625/50 Clips Do Not Play”.

Crash: Semaphore Limit Exceeded

If vvtr crashes, you might have exceeded the number of configured pollable semaphores. The log would appear as follows:

C 06-14:29:23.348170   1386 Failed opening semaphore file descriptor (sems open=147): No space left on device
A 06-14:29:23.348985   1386 FATAL SYSTEM ERROR:

To fix the problem, follow these steps:

  1. Edit /var/sysgen/master.d/usema and increase USMAXDEVS, for example, to 1050.

  2. Rebuild the kernel (autoconfig) and reboot the system to activate the change.

Crash: Audio Sync Problems When Audio Is Missing

VST crashes after a few seconds if you do not have an audio source. If you are having audio sync problems when there is no audio, do the following:

  1. Turn the audio off: in the /usr/vtr/config/device-defaults directory, edit the DIVO file and add: “0” 

  2. If you do not have an audio source, disable input audio by setting the unit control: ““ 

Crash: Audio Source Lacking

VST crashes after a few seconds if you do not have an audio source. To fix this problem, disable input audio by setting the unit control: ““ 

Configuring for Booting From a Backup Plex

The system normally boots from the primary root plex, that is, If the primary plex becomes unavailable, you can either label the disks and swap master and slave, or you can use the following procedure to set up the system so that it can boot from the secondary root plex, for example,

  1. From the System Maintenance Menu, choose Enter Command Monitor (5).

  2. Display the PROM environment variables:

    >> printenv 

    The swap PROM environment variable (which is set below) is not displayed because it is not saved in NVRAM.

  3. Reset the SystemPartition, OSLoadPartition, and root environment variables to the values of the disk partition that contains the alternate plex and the swap environment variable to have the value of the alternate swap partition. For example:

    >> setenv SystemPartition dksc(0,2,8) 
    >> setenv OSLoadPartition dksc(0,2,0) 
    >> setenv root dks0d2s0 
    >> setenv swap /dev/dsk/dks0d2s1 

  4. Exit the Command Monitor and restart the system:

    >> exit 
    Option? 1 
    Starting up the system... 

VST Crash Files

Inside the /usr/vtr/adm/crash directory is a subdirectory for each program that crashes. If a program crashes, a directory is dynamically created with that program name. Inside that directory a core file is created containing the crash information.

When VST detects a program crash, it renames the core file to core.number, where number is the next incremental number. This scheme prevents core files from overwriting each other.

VST crash files are saved to aid SGI support personnel in diagnosing VST software errors.