[HBASE-4936] Cached HRegionInterface connections crash when getting UnknownHost exceptions

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.92.0
• Fix Version/s: 0.94.0
• Component/s: regionserver
• Hadoop Flags: Reviewed
• Assignee: Andrei Dragomir
• Reporter: Andrei Dragomir
• Created: 02/Dec/11 14:56
• Updated: 12/Oct/12 05:35
• Resolved: 06/Dec/11 23:48

Description

This isssue is unlikely to come up in a cluster test case. However, for development, the following thing happens:

1. Start the HBase cluster locally, on network A (DNS A, etc)
2. The region locations are cached using the hostname (mycomputer.company.com, 211.x.y.z - real ip)
3. Change network location (go home)
4. Start the HBase cluster locally. My hostname / ips are not different (mycomputer, 192.168.0.130 - new ip)

If the region locations have been cached using the hostname, there is an UnknownHostException in CatalogTracker.getCachedConnection(ServerName sn), uncaught in the catch statements. The server will crash constantly.

The error should be caught and not rethrown, so that the cached connection expires normally.