Hi All, I am considering migrating my single (perfect) server setup (Ubuntu 18.04) to a Multiserver setup pretty much like the one in https://www.howtoforge.com/tutorial/ispconfig-multiserver-setup-debian-ubuntu/. I do however have a few questions for this great community: 1. Is it possible to add a 2nd web server (web02, for example) and have it replicate web01? The would be for high-availability purposes (if web01 goes down for some reason, web02 would serve the same websites) or for load sharing (with a load balance performing NAT at the edge of the network) 2. I read that the 2 mx server are replicated. Can they be used for high-availability and load balancing like the use case I mentioned for the web server? 3. If I create this multi server scenario, can I use the migration script to migrate all websites and mails to the new scenario? 4. Is there some other tutorial I should read for the high-availability scenario I am looking for? Thanks in advance to you all.
Yes, but you will need a file cluster for /var/www that is highly available, as the acme challenges for Let's Encrypt will otherwise fail (rsync is not fast enough) Yes, you can add a high available load balancer in front of the servers, so SMTP and IMAP is highly available for your users. Yes. Migrate to the main server, the mirroring to the secondary server will be done automatically. Search around the forum for some threads. E.g. https://www.howtoforge.com/community/threads/multiserver-setup.86820/ and https://www.howtoforge.com/community/threads/using-lets-encrypt-with-mirror-setup.86402/ Depends on your current knowledge
The 2 threads I referred to tell you more about it. TL;DR: You need a NFS share on a separate server that is mounted through fstab on your webservers. And of course you need to mirror the databases as well. It can be quite hard to maintain such a setup and when something goes down, it can be more difficult to resolve. Such a complicated setup can lead to more trouble in the long run. In my opinion, such a setup is only interesting when you host your own webshop with 1000+ orders a day, where it will cost more when the webshop is down for a few minutes than it costs to hire a team to setup, maintain, and monitor the environment. Another interesting thread: https://www.howtoforge.com/community/threads/ha-with-shared-storage.76865/
