Node Balancing (not load balancing)

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I have a US based client that has inquired about hosting a C5 8.2.1 website, I recently built, at
a second location, the host they are using has data centres across the US and on other parts of the world so finding a location isn't the issue or the provisioning of an integrated node balancer which is part of their infrastructure. The issue is with replicating any content changes onto the other node(s).Does anyone know of a plugin or extension that will allow automated replication of changes on one node onto a second or even tertiary node(s)? The node balancing isn't to provide load balancing but is to provide outage protection to make sure the site has very high availability. I have tried suggesting that changes to each could be made separately but they dislike that in case mistakes are made. The site has regular updates by multiple users of important corporate information and it is critical that it is up to date and always displays consistent data. Any ideas are welcome.

Sorry if its a long question but I wanted to make sure all the information is conveyed.

Thanks
Martyn

FaganSystems
 
blueatlas replied on at Permalink Reply
blueatlas
It seems that you will need to do this at the database and filesystem layers. MySQL replication isn't too difficult to set up, as long as you stick with a simple master/slave configuration:

https://www.digitalocean.com/community/tutorials/how-to-set-up-maste...

The file system could be handled with rsync. But remember, if you went this route and a switch to the slave occurs, any changes would then need to be migrated back to the master.

With that said, it sounds like your client wants to protect against a catastrophic failure of the master node. In practice, that's pretty rare. Perhaps you can get by with a regular (e.g. hourly) snapshot that is copied to a remote server. If that catastrophic event occurs, there's a little work to do, but downtime should be minimal. This add-on may help:

https://www.concrete5.org/marketplace/addons/backup-pro...
FaganSystems replied on at Permalink Reply
FaganSystems
Thanks for the reply, the Master-Slave setup is something I am familiar with in both the MSSQL and MYSQL worlds the trouble with that is that there could be several thousand miles between the two or more nodes, three possible locations currently being considered in the Linode network are Fremont, Dublin and Tokyo, this follows from a network failure of the Fremont DC network recently. Even though quite quickly resolved it did happen at the worst possible time for the client being right in the middle of a major corporate event.

Doing filesystem replication could get very messy if not handled carefully.

This is something I will explore further though, its all about risk vs benefit vs cost

Thanks for the reply