LCLS use of Alarm Handler

Overview
The EPICS Alarm Handler (ALH), developed at Los Alamos and Argonne, is an interactive graphical application that displays and monitors EPICS process variable alarm states. ALH communicates with the EPICS database using channel access function calls and displays a hierarchical, navigable tree of PVs and their alarm states, as specified by configuration files. ALH logs alarms and operator actions to CMLOG, and to its own log files. For a detailed description click [here.|http://www.slac.stanford.edu/grp/cd/soft/share/slaconly/alh/index.html#alhslac]

The Alarm Handler Browser run on the LCLS server as a background task connecting to a groups of PVs as listed above. This process is started from the laci account. The standalone process logs alarm messages to CMLOG and to the ALH Alarm and OpMod log files listed below in Table 1-3. This process is run without X displays, using Xvfb, a virtual framebuffer X server for X11.

Manuals

• Release Notes
• User's Guide
• Demo

Configuration

• LCLS Alarm Handling

References

• Author's Web Site
• EPICS Extensions Download
• EPICS Extensions Home Page
• EPICS Extensions at LCLS
• EPICS at LCLS

Note: Log files are accessible from the host lcls-dev only. Log files are not stored in CVS.

Alarm Handler Processes
There are 2 uses of the alarm handler for LCLS
1. The Alarm Handler Daemon Process: a single instance of this runs in without a visible browser. Its sole function is to log alarms to cmlog.

2. The Alarm Handler Browser: displays the alarm tree for operators and whoever else is interested. Can be started in 2 modes:

• SPY: read-only browser, in LOCAL mode, i.e. your alarm acknowledgements are LOCAL to your own browser.
• SUP: (supervisor) GLOBAL mode browser, i.e. your alarm acknowledgements are GLOBAL, written to the database. This mode should be used by operators in the control room only.

Start Alarm Handler Browser in Spy Mode

1. Log into any lcls host
2. lclsalh OR lclsalh spy

Start Alarm Handler Browser in Sup Mode

1. Log into any lcls host
2. lclsalh sup

Restart Alarm Handler Daemon process

1. Log into host lcls-prod01 using the laci account
2. cd /etc/init.d
3. ./st.alh restart

+Stop Alarm Handler Daemon process +

1. Log into host lcls-prod01 using the laci account
2. cd /etc/init.d
3. ./st.alh stop

+Start Alarm Handler Daemon process +

1. Log into host lcls-prod01 using the laci account
2. cd /etc/init.d
3. ./st.alh start

View Status of Alarm Handler

Start Archiver Watchdog
The cron job tscron.watchdog is use to monitor the status of the ALH Process running on the host lcls-dev. The cron job generates the log file /tmp/watchdog.log. This log file provides status information for diagnostic purposes only. The cron job also read and write the files listed in Table 1-3 below.

To restart a cron job:

1. login directly to lcls-dev from the laci account
2. crontab -r
3. cd /afs/slac/g/lcls/tools/alh/script
4. crontab < crontab.watchdog

Start Alarm Handler Heart Beat

System Administration

• Backups
• Log files