Quick environment shutdown

[billduty]

Wondering if anyone has used the -kill to stop their appservers and webspeed. Also proshut -F on the databases. Any ill effects of using these commands. Looking at a script to take the system down in a hurry during a power outage - limited UPS up time at the present.

Thx for any input.

 

[Rob Fitzpatrick]

You have so little runtime that you can't afford a normal shutdown? How long does that usually take? Granted it may take a little longer during business hours, if transactions have to be backed out, than it might during an off-hours maintenance window but I think at most it should be five to ten minutes.

If you don't even have that much runtime then your UPS is hopelessly overloaded, and gives you little real protection other than from the occasional power blip that causes a flicker of the lights. If I were you I'd be removing unnecessary load from the UPS, if possible, and getting budget for more UPS capacity rather than crashing my database.

 

[billduty]

You have so little runtime that you can't afford a normal shutdown? How long does that usually take? Granted it may take a little longer during business hours, if transactions have to be backed out, than it might during an off-hours maintenance window but I think at most it should be five to ten minutes.

If you don't even have that much runtime then your UPS is hopelessly overloaded, and gives you little real protection other than from the occasional power blip that causes a flicker of the lights. If I were you I'd be removing unnecessary load from the UPS, if possible, and getting budget for more UPS capacity rather than crashing my database.

Not my system - client was not aware until recently when they had an outage. New equipment is ordered. Looking for a safe way to bring down the production appservers, webspeed, and database without corrupting anything. That's why I'm inquiring about the -kill and the -F

 

[Cringer]

I'd be pretty wary of using -F to be honest. I use -by for a similar scenario (although it's my local databases and for when I'm going home! )

 

[RealHeavyDude]

Using -kill and -F is anything but a save way to bring the system down. Chances are that in killing processes you are damaging your database. A graceful shutdown of a system does take its time. Personally I don't care so much about the AppServers but I always try to shut them down gracefully - only when that fails I would use -kill and as a last resort a kill on the OS level.

I would never shut down the database with -F. For one it will set the damage flag on the database which you can only relieve doing an index rebuild and, as I explained, chances are that you really damage it. When you shut down the database in the midst of ongoing online transaction processing the database must back out all uncommitted transactions and that may take some time. If you don't permit the database to do so you will at least need roughly the same amount of time when you start or access the database next time because of the crash recovery taking that time.

Heavy Regards, RealHeavyDude.

 

[cj_brandt]

asbman for the app server has a -kill.

I thought the emergency shutdown killed all the connected sessions and didn't back out any transactions before shutdown. The transaction backout is handled during the next database startup. I did a test of proshut -F on a copy of the sports database and then started it back up. Promon screen 7 doesn't show a damaged flag being set. I am using 10.2B06.

Occasionally you will see a database bug where an emergency shutdown causes a db corruption - there was one listed on PEG a few days back. That would be my only concern.

I have seen several rc scripts where a regular database shutdown is invoked and then if the db isn't down after a set period of time, the emergency shutdown is used. Often the UNIX server would go down while the regular shutdown is still running.

 

[billduty]

Everyone - thanks for the input.

 

[RealHeavyDude]

cj_brandt you are completely right. proshut -F will not set the damage flag. I confused it with the -F on the truncate before image.

Heavy Regards, RealHeavyDude.