Can we configure Name Node High Availability using QJM on CDH 5 cluster running on MRv1?

[#1]

Can we configure Name Node High Availability using QJM on CDH 5 cluster having MRv1?

[#2]

Yes

[#3]

Thanks Michalis. However my understanding was that High Availability of NameNode can be configured only if we have YARN service in cluster. So can we configure High Availability of NameNode in MRv1 without YARN service?

Since am newbie, pls correct me if am wrong.

[#4 · Accepted solution]

Hello clouderazone,

HA configured via. QJM communicates through JNs so there is no dependency on MR version used.

[#5]

In more elaboration, any namespace changes on Active node is recorded by JNs and Standby node reads these edits from these JNs. And Standby node applies them to own namespace and try to be as close to Active node as possible. In failover scenario, SB node reads all edits from JNs before promoting it-self to Active so that there is full-sync before failover occurs.

Hope further details help with better understanding.