Re: Setting up a HA server with limited resources
Hmm. Gotta review CARP again, it seems. When did this go in? On Mar 23, 2008, at 2:29 AM, Ryan McBride wrote: On Sat, Mar 22, 2008 at 10:49:26AM -0700, johan beisser wrote: I would like to reach a state, if possible, in which load balancing is performed, but at the same time, if one machine fails, the other will automatically take over. I believe this setup is also very useful when deploying updates. You're screwed on the load balancing without a 3rd system in the mix. Preferably 4 systems, so you've got failover between the firewalls. That's not the case anymore - see the IP BALANCING section in the carp(4) manpage. (there are a few caveats, first and formost being that your layer 2 network will have to cooperate)
Re: Setting up a HA server with limited resources
On Sat, Mar 22, 2008 at 10:49:26AM -0700, johan beisser wrote: >> I would like to reach a state, if possible, in which load balancing is >> performed, but at the same time, if one machine fails, the other will >> automatically take over. I believe this setup is also very useful when >> deploying updates. > > You're screwed on the load balancing without a 3rd system in the mix. > Preferably 4 systems, so you've got failover between the firewalls. That's not the case anymore - see the IP BALANCING section in the carp(4) manpage. (there are a few caveats, first and formost being that your layer 2 network will have to cooperate)
Re: Setting up a HA server with limited resources
On Mar 22, 2008, at 5:44 AM, Rico Secada wrote: Hi. A customer with very limited resources needs to set up a high available system running apache, mysql, postfix and dovecot and I have gotten the task. it's doable, but the unanswered question is what do each of these components have to do with one another? What exactly are you trying to do? I have only two Pentium 4 machines at my disposal, and I have begun researching how to make them work with load balancing and fail safe operations at the same time. I have one public IP address available. This would be a CARP component. I would like to reach a state, if possible, in which load balancing is performed, but at the same time, if one machine fails, the other will automatically take over. I believe this setup is also very useful when deploying updates. You're screwed on the load balancing without a 3rd system in the mix. Preferably 4 systems, so you've got failover between the firewalls. Any advice on how to implement such a setup? First, figure out what they're asking for. Then separate the problem in to component issues. - MySQL master-master replication - HA Heartbeat (linux-HA is a good start on how to do this) - Dovecot IMAP with MYSQL as a back end -- this is usually just for AUTH. Where does dovecot keep its files? Last I looked, it couldn't shove them in to MySQL, or pull the email out.
Re: Setting up a HA server with limited resources
On 2008-03-22, Rico Secada <[EMAIL PROTECTED]> wrote: > Hi. > > A customer with very limited resources needs to set up a high available > system running apache, mysql, postfix and dovecot and I have gotten the > task. > > I have only two Pentium 4 machines at my disposal, and I have begun > researching how to make them work with load balancing and fail safe > operations at the same time. I have one public IP address available. > > I would like to reach a state, if possible, in which load balancing is > performed, but at the same time, if one machine fails, the other will > automatically take over. I believe this setup is also very useful when > deploying updates. > > Any advice on how to implement such a setup? carp IP balancing.
Setting up a HA server with limited resources
Hi. A customer with very limited resources needs to set up a high available system running apache, mysql, postfix and dovecot and I have gotten the task. I have only two Pentium 4 machines at my disposal, and I have begun researching how to make them work with load balancing and fail safe operations at the same time. I have one public IP address available. I would like to reach a state, if possible, in which load balancing is performed, but at the same time, if one machine fails, the other will automatically take over. I believe this setup is also very useful when deploying updates. Any advice on how to implement such a setup? Best regards. Rico.