Sun Directory Server - Referrals Feature

I was recently involved in a Sun Directory Servers Multi-Master Replication (MMR) Re-Configuration exercise in the Philippines. After analysis, the problem is not a major. We only need to put in place a NTP server to sync-up the Directory Servers. Finally, we need to initialize the suffix again since they are out-of-sync for quite some time.

The Directory Servers have been in Production for a number of years and there are LIVE applications accessing the Directory service.

If we were to initialize the suffix from Directory Server 2 (the Source) to Directory Server 1, then Application 1 will not be able to access Directory Server 1 during initialization.

We have a problem. This particular suffix hosts around 17 millions entires and it would take us a number of days to complete initialization.

A workaround is to ask:

1. the Network Team to grant Application 1 access to Directory Server 2 directly

2. the Application Team to change their code in Application 1 to point to Directory 2

This is painful!

A better workaround is to make use of the Referral feature in Sun Directory Server.

Referrals can also be used to temporarily point a client application to a different server. For example, you might add a referral to a suffix so that the suffix points to a different server while backing up the contents of the suffix.

Read more here.

Nice!