Thanks all. Some good ideas. On 26/01/2010, at 7:12 AM, Chuck Hill wrote:
> On Jan 25, 2010, at 5:35 AM, Pascal Robert wrote: > >> Le 10-01-25 à 01:40, Lachlan Deck a écrit : >> >>> Hi all, >>> >>> just polling for ideas / techniques people use in detecting dead instances. >>> Naturally when there's lots of instances running in deployment it can be >>> hard to know if a particular instance has locked up for some reason (and >>> this can sometimes have a flow on affect with the adaptor). >> >> >> We use Nagios with the check_http module (bundled with the default Nagios >> plugins). We check a DirectAction that simply returns "OK" and nothing else, >> but we will add two more checks : one that will fetch a very small dataset >> with EOF and another one by raw JDBC. By doing one check by EOF and one by >> JDBC, we can see if it's a EOF deadlock or not. The most important thing: >> don't check a page that use sessions! If you try to stop an app cleanly but >> Nagios or other tools keeps creating new sessions, you might have a fun time. >> >> As for checking specific instances, you can specific the instance number in >> the URL, but the problem is that the HTTP adaptor will send you to another >> instance if the checked instance is dead. BUT you can use Wonder's variant >> of JavaMonitor to check if a specific instance is up or not. > > Or, more easily, have the instance number returned in the response (e.g. "4 > OK") so that the script can verify that the result is from the correct > instance. > > Chuck > > >> Nagios is my friend! We are currently checking 211 services with it (disk >> space, Oracle listener port, all apps, load, ntp, etc.). >> >> ---- >> Pascal Robert >> prob...@macti.ca >> >> AIM: MacTICanada >> Twitter : MacTICanada >> LinkedIn : http://www.linkedin.com/in/macti >> > > -- > Chuck Hill Senior Consultant / VP Development > > Practical WebObjects - for developers who want to increase their overall > knowledge of WebObjects or who are trying to solve specific problems. > http://www.global-village.net/products/practical_webobjects with regards, -- Lachlan Deck _______________________________________________ Do not post admin requests to the list. They will be ignored. Webobjects-dev mailing list (Webobjects-dev@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/webobjects-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
