I help manage a few hosted commercial applications, and we have a lot of manual processes involved when doing new customer-instance deployments into the shared (multitenant) environment. Allow me to describe the most relevant features, and then we can talk about the tools.
We have an application on AIX, that requires dozens of changes to config files (some plain text, some XML) as well as a good number of commands to be run on multiple servers - some to start the new instance, some to restart our shared authentication and reporting engines, etc. The config changes follow templates, of course. The servers in question will also depend on the initial conditions specified by the implementer/deployer - we may choose to deploy a given customer to our servers in Europe, or one set of servers may be active-active whereas a different set of servers is active-passive - in short, there's a lot of complications.
We have another application that run on IIS 6 and SQL. The DBAs don't want any automation of the SQL components and that's fine with me, but automating the IIS bit would be great. For a new customer instance, we make a filesystem copy of a template Virtual Directory target named after the new customer, make a new AppPool to match, edit a VirDir template .xml file to replace the filepaths and AppPool names with the new ones, and then make a new VirDir from the modified template XML to point to the new filesystem folder and app pool.
For the first case, something like ControlTier or Chef might be good. For the second, the new(ish) Web Deploy from MS would probably do a good job.
Has anyone used these tools or others to do something similar for applications? More of a nice-to-have, not a fixed requirement - Has anyone used anything that works on both platforms? I'm looking for something free, because the official word is that within a year, we will have whatever HP has renamed the OpsWare suite, which should be able to do stuff like this.
Edit - based on someone's suggestion, looking at CFengine for the AIX application, it doesn't seem to address my pain. The problem isn't keeping a given config synced across dozens of servers, we have rsync for that. The problem is that onboarding a new customer instance touches dozens of files, putting pieces of the same or similar information into them - some are new stanzas in existing files, some are new files, and some are new directories. This is a several-hours-long process that is also error-prone because it's mostly done by hand. I guess I'm looking for config-file generation and management. I have built a small Perl script to do something similar for a much smaller case - it binds a CSV file into variables, and then does a copy-and-search-and-replace from a set of template config files. I could probably do the same here.