On Thu, 2005-12-15 at 21:21 -0500, Bill Mathews wrote: > Hans Engelen wrote: > > >Could you provide a little more information on the issue at hand ? > > >A short description of your setup would help. We are defenitly talking > about clustering here right, >not load balancing ? The double ping > response issue sounds more like a load balancing issue. > > > Well, it's allegedly a failover cluster. I don't control the Microsoft > end of it and I've been told it's a failover. The only details I have is > that we're monitoring it across the Internet, along with a few hundred > other machines and that site is the only one giving us this trouble. > It's somewhat odd. > > Setup is nagios latest running on Debian stable, not sure what other > setup info would help.
Strange. I would agree with Hans that it sounds a lot like a MS NLBS (Network Load Balance Services) cluster and not a MSCS (MS Cluster Services). However, since you say your monitoring from across the Internet and not the local network the only way that I know of to get that kind of response would be to an MS NLBS on a VMware ESX or GSX server. Though, it's potentially possible to elicit that kind of response from a even from a non-local machine. They may be running a NLBS "failover" cluster and not a true MSCS. NLBS can run in a full load balance or in an active / passive (aka failover) configuration. As NLBS does some stupid packet magic to get the clustering to work it can have undesired side effects of all nodes in the cluster replying to pings. If you can get your customer to give you more information on the cluster, I bet they will tell you that it is an NLBS cluster in unicast mode. You might suggest to them that they work with their network techs to switch over to multicast mode, that should hopefully help a little with the problem. A better suggestion is for them to get a hardware load balancer instead of using Microsoft's NLBS solution. As we've discovered on our network, it causes a lot of problems on the media layer that kills some network security. -Andy- ------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Do you grep through log files for problems? Stop! Download the new AJAX search engine that makes searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! http://ads.osdn.com/?ad_id=7637&alloc_id=16865&op=click _______________________________________________ Nagios-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/nagios-users ::: Please include Nagios version, plugin version (-v) and OS when reporting any issue. ::: Messages without supporting info will risk being sent to /dev/null
