Hi all, this is the configuration I have setup. 3 Debian ISPConfig servers clustered together with Web, DB, DNS ect.. all configured and without ISPConfig web interface installed 1 Debian ISPConfig server configured as the main interface server. I installed the interface server first and then installed and added the other 3 servers to a "multi-server configuration" When I look at the System tab in the interface I can see all 4 servers, if I make any changes such as add clients and websites these are all replicated to the other 3 servers. Ok, so what doesnt work or perhaps my misunderstanding, if I check the "Main Config" and look at the Default Webserver and Default Database Server, I am unable to change this to any of the other 3 servers, they are not in the list. The reason this is going to be an issue for us is that we have 1 standalone server at the moment which runs a bunch of web sites which I want to migrate over to the new cluster and it would look like at the moment it would try to migrate them to the interface server rather than the webserver cluster. Any advice or comments??? Many thanks
Are those three servers set up as web server and database server in Panel | System | Server Services?
Hi Taleman, yes those 3 servers have web/db/mail/dns/file set to yes. If I create a new client on the wsc (web server control) server its replcated to the 3 ws (web server) servers, so they are linked up in some ways.
Ok, so you set the three servers to be mirrored. A mirror means that it gets all configurations of its master automatically, therefore it makes no sense to be able to select them as default systems and only the master of the mirrors can be selected there, which is the case on your system. If you want to be able to individually select that e.g. site abc.tld goes to server 2 or 3 and not 1 + 2 + 3, then server 2 can not be a mirror of server 1 (same for server 3) and you must disable mirroring under system > server services for server 2 and 3.
Thanks @till, I understand that part of it now. So I was planning on the master server just being an interface server and as such it does not have the same specification as the web cluster servers, its not as fast and does not have the HDD space to host websites. If I use the Migration tool to migrate websites to this new cluster, how is that going to work? If I set a remote user on the interface server will all 3 cluster members get that user? and then in the migration tool I set the target to be one of the cluster members? Will it work that way or does the migration tool need to communicate with the interface server?? Many thanks.
Ok, so I assume you have: Server 1: Interface Server 2: First Hosting Server Server 3: Second Hosting server In this case, you should configure Server 3 to be a mirror of Server 2 and not to be a mirror of the Interface system, as the interface system is just the interface and does not host any websites. In general, you should consider if it makes sense to make Server 2 and Server 3 mirrors, in most cases, it's better to have them just as non-mirrored slave systems of Server 1 and then host some sites on Server 2 and other sites on Server 3. In theory, it always sounds nice to have servers 2 and 3 as mirrors for redundancy. Still, in reality, you will likely see that such a mirrored setup causes more downtime due to the added complexity of having MySQL master/master replication for website databases, and the need for mirroring the filesystem of the nodes will cause the overall system to be slower. So you should really consider if this setup is the optimum for your needs or if it's better to have the additional systems just as non-mirrored slaves connected to that master plus a good backup strategy in case server 2 or 3 fails. Regarding Migration Tool, the Migration Tool always connects to the master, it will then ask you to which node the emails, websites etc. shall be copied to. In case or mirroring, it would show only the master of the mirrors, similar to what I explained in my last post about default servers.
As always thanks for your comments @till. Just for clarity this is our setup: Server 1: Interface only Server 2: First Hosting Server Server 3: Second Hosting Server Server 4: Third Hosting Server Website DB's are clustered with Percona which works perfectly and is so easy to manage and to grow the deployment, Website files are clustered with Unison, First hosting server replicates real-time down to second and third and our monitoring software activates Unison on the second server to replicate to the third if the first server goes offline and then reverses it when the first server comes back online. Does this change anything from what you have said above, I just wanted the interface only server to be used for the admin/configuration work and the 3 hosting servers to just host the sites. The configuration we have at the moment works but the migration we need to do adds complexity I guess. Thanks
If you're happy with your percona and unison setup, then that's fine of course. Ok, so server 2 is the 'master' hosting server, which means server 3 is a mirror of server 2, and server 4 is a mirror of server 2 as well. This does not add complexity for the migration tool, you let it connect to server 1, the tool will then show you available servers as target and you choose server 2 as that's the 'master' of the hosting nodes.
Thats great @till, I think I have modified the configuration and it looks good now. And I better understand how the multi-server architecture works now. Many thanks for your help. A little bit more testing and then I can purchase the migration tool and migrate everything over. Thanks.
