Thank you Oscar, for your information.
2008/4/8 Oscar Haeger <[EMAIL PROTECTED]>: > Hi. > Heartbeat is usually a private network between the nodes, used to send > data about which nodes are alive. You'll want a low latency network for > this. Google for clusters and heartbeat and you'll find lots of information > I'm sure. > > Clusters can be used as High-Availiblity where server B is indeed just a > backup, but it can also be used as High-Performance where two or more > servers share the requests between them. Obviously the performance will > degrade if parts of that cluster goes down. So yes, B can both be a backup > and an equally performing server, depending on your setup. > > I'm a bit out of my compentence area here as I haven't done webserver > clustering, but I do believe the general principle is about right. I'm sure > someone on this list will correct me where I'm wrong. > > Cheers, > > Oscar > > ________________________________ > > Från: Ch Praveena [mailto:[EMAIL PROTECTED] > Skickat: ti 2008-04-08 10:47 > Till: users@httpd.apache.org > Ämne: Re: [EMAIL PROTECTED] Split-brain problem. > > > Thank you Oscar, > > As I am new to clustering Tomcat, Let me know some information about > Heartbeat too.. > > And according to your information, Is that Server B a backup for Server > A(So that when A fails, B attain its responsibilites) or an equally > performing server with A. > > > > > 2008/4/8 Oscar Haeger <[EMAIL PROTECTED]>: > > > From my experience with clustering that is when the connection > between parts of the clusters are lost and they can't agree on which one is > supposed to keep serving the data. The most common way around it afaik is to > have a priority and heartbeat between the nodes and allow them to kill each > other off (something like STONITH = Shoot The Other Node In The Head) or > similar. > > So, if we have two servers A and B and a heartbeat (with STONITH) > between them and node A misses a few heartbeats (perhaps a lockup, perhaps > something else), then node B will reset node A and take over that nodes > capabilities. > > This is without reading about Terracotta so things might be > different there, but that's the split-brain problem from my experience. > > Hope this helps > > Cheers > > Oscar > > ________________________________ > > Från: Ch Praveena [mailto:[EMAIL PROTECTED] > Skickat: ti 2008-04-08 09:30 > Till: users@httpd.apache.org > Ämne: [EMAIL PROTECTED] Split-brain problem. > > > > > Hi all, > > While going on with Terracotta article, > -- > http://www.terracotta.org/confluence/display/explore/How+Terracotta+Works, > For implementing application server clustering, I found this > phrase, "Split-brain problem.".. > > Please let me know about this in detail.. > > > > Regards, > > Praveena Chalamcharla, > Securview.... > > > > --------------------------------------------------------------------- > The official User-To-User support forum of the Apache HTTP Server > Project. > See <URL:http://httpd.apache.org/userslist.html> for more info. > To unsubscribe, e-mail: [EMAIL PROTECTED] > " from the digest: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > > > > > -- > Regards, > > Praveena Chalamcharla, > Securview.... > > --------------------------------------------------------------------- > The official User-To-User support forum of the Apache HTTP Server Project. > See <URL:http://httpd.apache.org/userslist.html> for more info. > To unsubscribe, e-mail: [EMAIL PROTECTED] > " from the digest: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > -- Regards, Praveena Chalamcharla, Securview....
