XRT HOWTO --- Restart HK at ISAS

K. Glotfelty, D. McKenzie, K. Reeves, M. Weber; 2007-Aug-16

If the XRT HouseKeeping (HK) appears to have stopped working, one possibility is that the HK processes at ISAS have hung. This HOWTO explains how to restart those processes.

NOTE (added 2008-11-10 by K. Reeves): This procedure only restarts the HK is cron jobs are stuck at ISAS. The housekeeping software has been reconfigured, so that this is much less likely. If the housekeeping is not updating, it is probably due to the cron jobs at SAO. Contact xrt_manager@head.cfa.harvard.edu if this appears to be the case.


There are cronjobs at ISAS that run xskim and related software routines in order to collect the HK information from the telemetry pipeline. These cronjobs run about once per hour. There is another cronjob at SAO that pulls that info to the SAO XRT HK website, and that cronjob also runs about once per hour. Therefore, in order to fix the hung HK jobs, you only have to kill the processes. The cronjobs will automatically restart everything within an hour. It may take up to about 2 hours for the new HK data to appear on the SAO webpage. However, it is also possible that the new xskim and mergeband processes will start immediately, and you do not want to kill the new ones.


  1. Log on to xrtco workstation. Check the directory /soda/solarb/xrt/status/yyyy/mm/dd.
  2. Log into ISAS workstation "norway". You will have to log in to the gateway machines (ssh1, ssh2 or ssh3) as user sbusxrt first.
  3. Look for the mergebands and xskim processes, and note their process ID numbers:
  4. Kill the xskim job. (Using the ID number from this example...):
  5. Wait until after any mergeband jobs are done.
  6. Verify that the file ~/mworking is removed.
  7. Send email (To: xrt_manager@head.cfa.harvard.edu; Cc: xrt_co@solar.isas.jaxa.jp) announcing the time that you killed the HK processes, so that others do not also try to fix the problem. In the email, also remind people that it may take up to about 2 hours before the new HK info is transmitted to the SAO HK website.