The issue

It appears that Notes clients are caching Domino server addresses persistently - i.e. even after Notes client restart, the client will remember previous Domino server addresses.

This can be particularly annoying when a Domino server has been assigned a new IP address. The Notes client will insist on using the old IP address, even if DNS is pointing to the new one. The Notes client is preferring the cached item over DNS.

Neither a Notes client restart, nor deleting Cache.NDK will make the Notes client forget the cached item, and fetch the new address, resulting in the Notes client being unable to reach the Domino server (forever).

Another issue is that the Notes client is trying to reach Domino servers that no longer exist. This is causing a Notes client to "hang", until it times out. Overall, this may be one of the main reasons for sluggish behavior.

Proposed solution

1. Whether persistent caching of Domino server addresses is still useful nowadays, should be re-evaluated. (Dial-up connections have become extremely rare). Volatile (in-memory) caching may be sufficient.

2. Upon Notes client restart, the client should try to lookup DNS, and prefer DNS over cache.

3. Add a setting to ignore the persistent cache completely, assuming there is also an volatile (in-memory) caching, which the client will be able use for performance reasons.

4. Introduce Policy Settings to control the caching behavior.

5. If persistent caching is still needed, there should be a way to remove old servers which no longer exist. (no manual fiddling in local databases, it should be a scalable solution)

[ Toni Feric, Belsoft Collaboration ]