In this edition of the Domino Mailbag, expert Chuck Connell tackles reader questions on upgrading to Domino 8.5 with clustered servers, using the Domino Internet Cluster Manager and more.
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My company is planning to upgrade our Lotus Domino servers from Version 7 to Version 8.5. We currently have four servers where Server 1 and Server 2 are clustered, while Server 3 and Server 4 are also clustered.
We have one admin server and one SMTP server. We are planning to go with 64-bit OS. What do you suggest as the best upgrade path?
If you can afford some extra hardware, my opinion would be to bring up the new servers before taking down the old ones. This will give you a higher probability of no user downtime.
Create new servers Server 5 and Server 6, then install your new OS and Domino 8.5 onto them and add them to the first cluster. Users should notice no difference, since the old servers are still running. After a few days, when everything is stable, switch your admin processing to one of the new servers -- assuming that your admin server was in this cluster. When that is stable, shut down Server 1, but keep it ready to restart if needed. When everything is stable again, shut down Server 2, keeping it ready to restart.
When the first cluster is stable, repeat the process described above for the second cluster and the SMTP server with Server 7 and Server 8. Wait a few days between each step, so that you're not fighting multiple problems at once. When all the old servers are shut off, you're done! Keep the old servers in place and ready to go for 90 days or so, then back them up and recycle them.
Note: I'd do a little research about whether or not a 64-bit solution is really going to be faster. I've read some IBM TechNotes that say it may not make much of difference for Domino performance.
In one to one Domino clustering environment, if the server that all users point to is down, does the other server automatically step in or is there a simple switch?
Yes, that is the point of clustering. The Notes client maintains a list of servers in a cluster. If one of the servers goes down, Notes knows which other servers to try. Remember that the cluster has to be up and each Notes client has to connect for long enough to build this list. If a Notes user connects to a cluster that they've never accessed before, and one of the clusters servers is down, the clustering failover may not work correctly. However, this is a rare situation.
In cluster servers, do the same documents have the same Note ID or is it different and why?
The Note ID is different because it is a unique identifier within a database. Another reason it is different is that two servers may join a cluster, when they were previously separate. Each document would have its own Note ID before the servers joined the cluster and all the Note IDs cannot change the moment the servers become part of the same cluster.
Remember that Note ID is just one of the IDs associated with a document. There are also replica IDs and universal IDs. The whole scheme is fairly complicated. If you want to read a detailed explanation, read Anatomy of a Note ID,written by my friend Martin Cox.
When an intranet Domino website is hosted on multiple servers within the same domain (through replication) and all users are using the same URL, will they be routed to the nearest available Domino server hosting the website?
No, they will not be routed automatically. Domino has no built-in mechanism to do what you describe. This really can't happen because how could an individual server know what other servers might be closer than itself? Also, you don't want users to be directed to the closest available server. That server might be 99% busy with other users.
In this case, you want to use Domino Internet Cluster Manager, which accomplishes what you have in mind. It sits outside your Domino Web servers and directs traffic to the best available server, based on various criteria that you can control.
|ABOUT THE AUTHOR:|
Chuck Connell is president of CHC-3 Consulting, which helps organizations with all aspects of Domino and Notes.