HBase: what is NotServingRegionException?

Question

What is the NotServingRegionException in HBase?

My HBase cluster has been working fine, but over the last few days, a strange error message like this one below keeps popping up:

Failed 180 actions: NotServingRegionException: 180 times, servers with issues: x.y.z.a:60020,

I'm using Thrift to insert data into HBase. It looks like most of the data inserts fine, but the job still throws this "error".

Searching on the Internet reveals that this exception may be related to a region split, but how do I fix HBase or my script so that this Exception is not thrown any more?

Answer 1

If you see this too often, it looks like your regions are split / moved between region servers too often.

Consider pre-creationg regions or using custom region splitting policy.

Please note default region splitting policy is changed starting from HBase 0.94, I spent some time to understand this issue. Here is right article, you need 'auto splitting' chapter.