NethServer Version: NS8 Module: Roundcubemail and Mail
Hello.
I have a task to create a fault tolerant cluster with web client.
I have deployed 2 NS8 servers so far.
So far only MX records are configured on each of the servers.
So far I have encountered the following problems:
Obviously, the Roundcubemail address should be one. I have deployed Roundcubemail on both servers. And on both servers I specified the same address: rmail.mymail1@example.com.
But if I disconnect the main server, the site doesn’t open. How do I solve this? With a load balancer or with DNS records?
I don’t quite understand how to configure the departmental mail server. Do I need to tell it to forward to the main server or does it synchronize itself?
So NS8 has load balancer functions in it or not?
And another interesting question: if the main server goes down, how do you manage it?
One way could be switching one of the worker nodes to leader: In case unreachable leader node promote a worker node to leader by running switch-leader command (with required parameters) on every worker node.
you can handle fault tolerant scenarios using DNS.
set MX1 for the first server and MX2 for the second server, with different tl settings.
as for the webmail clinet.
configure the same domain, with both ip address for the 2s ervers, if one goes down, dns records will point to the second server.
thats the simplest way. you can hweover implement a sort of load balancer infrotn of your servers, to handle and route traffic for DNS based on which server is available.
that might be a more complex and complicaed setup.
As far as I understand you can put a load balancer like NGINIX or opnsense in front of the servers and it will be fine.
The second question remained:
2. In the nethserver mail settings, there is a button Relay tab button. Do I need to configure relay for synchronization?