HA Experiences

[craigyk]

I'd like to ask what other people's experiences have been with HA, and how they've done their setup.

Personally, I tried to use it but just had too many problems and it made my overall infrastructure less reliable.  I had two zentyal instances doing HA with AD, DNS, DHCP, NTP, and routing.  My biggest problems were related to DHCP and DNS.  It seemed I sometimes got split-brain where both DHCP servers were running, or it would switch DHCP from one server to the other for no apparent reason.  This might have been OK, but Zentyal seemed to have problem keeping DNS in sync between the two machines with DHCP and DynDNS.  DHCP leases from one server would correctly sync forward and reverse-zone entries between both servers, but not the other way around. 

Though overall, HA is very promising, I eventually shutoff the second server as my two servers bickered too much and caused a lot of network problems.  Maybe adding a third server for better consensus might have helped?  Curious what others have done.

[Lonniebiz]

What do you mean by HA? High Availability?

[Lonniebiz]

Since upgrading to 3.4, I'm having the same issues you mention.

I have another dhcp pool on my additional domain controller. When workstations switch pools, I'm having all kinds of issues.

Sometimes the users can't login to their workstation, and sometime they can't access file shares that are on the windows servers.

I can't figure it out. All worked fine in 3.3.10

[craigyk]

Since upgrading to 3.4, I'm having the same issues you mention.

I have another dhcp pool on my additional domain controller. When workstations switch pools, I'm having all kinds of issues.

Sometimes the users can't login to their workstation, and sometime they can't access file shares that are on the windows servers.

I can't figure it out. All worked fine in 3.3.10

3.4 has been working well for me since I turned off the second instance being used for high availability.  I did figure out that zentyal creates a /24 reverse zone entry for each DHCP pool in the dhcpd.conf file.  Since I'm using 192.168.0.0/16  that means I need to add a fake dhcp pool entries to add reverse zones for my static dhcp addresses (ie 192.168.0255-192.168.0.255).  Personally, doing it manually, I would have just created a single .168.192.in-addr.arpa entry in the dhcp config to cover the entire subnet.  I also added "anchor" DNS entries to ensure that reverse zones are also created for DNS.  Not sure if this is still needed, if it is a bug, or if has been fixed.  My take is that development was centered around the sue of /24 subnets.