I'm pleased to report that I've (at last) had a measure of success with the AppFabric installer :-)
I mentioned in my last entry that I'd posted on the MSDN AppFabric Caching forum about the problems I'd been having with the installer. I also made two of my installation logs available. I'm indebted to Rahul Kaura from Microsoft, who pointed out that these were AppFabric general installation logs and steered me towards the cache-specific installation logs. These logs are found in the same place as the AppFabric logs i.e. your %TEMP% folder, are called DistributedCacheAppServerConfig(DateTime).log and I've found them invaluable in diagnosing and fixing installation problems.
So what were the problems I was having? From reading the log they seem to be largely around permissions to the Registry:
2010-01-06 11:52:52, Info DCACHE Adding access for NT AUTHORITY\NETWORK SERVICE on registry key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft Distributed Cache\Version
2010-01-06 11:53:16, Error DCACHE System.InvalidOperationException: This access control list is not in canonical form and therefore cannot be modified.
at System.Security.AccessControl.CommonAcl.AddQualifiedAce(SecurityIdentifier sid, AceQualifier qualifier, Int32 accessMask, AceFlags flags, ObjectAceFlags objectFlags, Guid objectType, Guid inheritedObjectType)
at System.Security.AccessControl.DiscretionaryAcl.AddAccess(AccessControlType accessType, SecurityIdentifier sid, Int32 accessMask, InheritanceFlags inheritanceFlags, PropagationFlags propagationFlags)
at System.Security.AccessControl.CommonObjectSecurity.ModifyAccess(AccessControlModification modification, AccessRule rule, Boolean& modified)
at System.Security.AccessControl.CommonObjectSecurity.AddAccessRule(AccessRule rule)
at Microsoft.Data.Caching.InstallConfig.Program.SetResetLocalPermissions(Boolean grant)
at Microsoft.Data.Caching.InstallConfig.Program.Main(String args)
2010-01-06 11:53:16, Error DCACHE Unexpected Error: This access control list is not in canonical form and therefore cannot be modified.
2010-01-06 11:53:16, Info DCACHE Configuration failed, Rolling back...
which is sort of annoying as I've been running the installer under an account that is a Domain Administrator, and the Domain Admins group is part of the Administrators group on each of my cache servers. The solution was to add the account I'm using to install AppFabric to the ACL for HKEY_LOCAL_MACHINE with full permission.
The installer still reports that it fails to configure AppFabric, but this is because the log includes a Warning that the Windows Firewall is disabled, which I'm reasonably sure I can ignore.
So, I now have an AppFabric caching cluster with three servers. Onward to actually using it!