[YARN-5404] Add the ability to split reverse zone subnets

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: YARN-4757
• Assignee: Shane Kumpf
• Reporter: Shane Kumpf
• Due: 31/Jul/16
• Created: 19/Jul/16 20:12
• Updated: 02/Aug/16 11:48
• Resolved: 02/Aug/16 11:48

Description

In some environments, the entire container subnet may not be used exclusively by containers (ie the YARN nodemanager host IPs may also be part of the larger subnet).

As a result, the reverse lookup zones created by the YARN Registry DNS server may not match those created on the forwarders.

For example:

Network: 172.27.0.0
Subnet: 255.255.248.0

Hosts:
0.27.172.in-addr.arpa
1.27.172.in-addr.arpa
2.27.172.in-addr.arpa
3.27.172.in-addr.arpa

Containers
4.27.172.in-addr.arpa
5.27.172.in-addr.arpa
6.27.172.in-addr.arpa
7.27.172.in-addr.arpa

YARN Registry DNS only allows for creating (as the total IP count is greater than 256):
27.172.in-addr.arpa

Provide configuration to further subdivide the subnets.