MFXP database 2

[nix45]

We're running MetaFrame 1.8 and are about to set up a new Citrix XP farm with 3 load balanced servers. One of the new features in MetaFrame XP is that the farm settings are stored in a single database. I'm really not crazy about this as it creates a single point of failure it seems. What happens if this database goes down? Will users still be able to log in? Which database would you recommend for 3 servers and about 100 concurrent users?

Thanks,
Chris

 

[JeffHicks]

The Citrix servers store a local cached copy of the database so that if the database and/or database server are unavailable, they can still accept connections and function properly. I believe the database can be unavailable for 48 hours before it causes any real problems. Good backup and restore procedures for the database should keep you from hitting that time out in the case of a failure. I have used SQL for all of my farms. That small of a farm should work with an Access Database, but I prefer the reliability of SQL Server or Oracle, even for a small farm.

 

[nix45]

So every Citrix server copies the entire database and keeps a copy for 2 days? I haven't done any SQL before, but I know that I can get the database up and running with minimal effort. After the database is up, is there any other SQL-related tasks that I'll have to do? If not, I'll just use SQL instead of Access, because we already have an SQL Server 7.0 database for another application on the network.

Thanks,
Chris

 

[joergguenther]

I recommend using SQL as well. You have many features that Access simply cannot give you. You can for example replicate the entire db onto a separate server (yes, Access can do that as well but is not as robust). Furthermore you can automate a lot of administrative tasks such as re-indexing, purging of log files etc.

Regards,

Joerg

 

[JeffHicks]

I know a minimal amount about SQL administration and have never had a problem. Just follow standard best practices for maintaining a SQL database and you should be fine.

 

[nix45]

If I use SQL and replicate the database to another server, if the main SQL server goes down, can I tell MetaFrame to use the backup?

Chris

 

[JeffHicks]

Yeah. The command you would need to run on each server is dsmaint. you can do a dsmaint -? to get the various usages. I could get you the specific command, but you might learn more by just doing the -? switch and seeing all the things that dsmaint can do. I have moved my farm from one database to a copy and back, and from one SQL server to another several times and have never had an issue. I did this both to test and verify it worked, and also when I had a critical hardware failure on my production SQL server. I was able to restore the previous night's backup to a secondary SQL server and point the farm to the secondary. I only did this because I wanted to take the opportunity to rebuild the production SQL server to our new standards rather than simply restoring it. Once I had done that, I moved the farm back to the newly rebuilt production SQL server. All of that can be done without rebooting Citrix. It rocks.

 

[nix45]

Joe, I ran a quick test to see if the servers actually do hold a cached copy of the database, but it didn't work. I took my Citrix box with the Access db offline, and none of the clients could log into any published apps. They get an "I/O Error". Is there some configuration that I have to set to get the servers to hold a cached copy of the db?

Thanks,
Chris

 

[JeffHicks]

Not at all. It is part of the Citrix architecture. Check the following path to see if you have a imalhc.mdb X:\Program Files\Citrix\Independent Management Architecture where X is your system drive letter. You should have imalhc.mdb, imalhc.ldb, and imalhc.dsn files there. Those are your local host cache files. Your error sounds like your Client is configured to only point to your "main" Citrix server. Verify that your clients have all of your Citrix servers listed in their connection settings.

 

[nix45]

Thanks, it was the client. The client was set to use the default "ica" in the server location, and the DNS round-robin I set up isn't working. The ica host only resolves to one server for some reason. Thats another issue I have to look into.

Chris