Weird instance numbers in the OID SNMP objects

Hi,

I'm querying the status of our Virtuals, Pools, PoolMembers on our LTM. I use SNMP to do that and noted a weird behavior with some objects like ltmPoolMemberStatServerBytesIn

Usually, the instances of the objects under

ltmPoolMemberStatServerBytesIn

are formatted this way: If the name of the pool member is:

/Common/vmp-ds1-01:9443

then, the instance number is:

 18.47.67.111.109.109.111.110.47.118.109.112.45.100.115.49.45.48.49.9443

where:

• the first number is the length of the member name (/Common/vmp-ds1-01). 18 here.
• the other numbers are each character in ASCII
• finally the port

It is great. But sometimes, the instance is way longer and is prefixed with the pool name. For example

15.47.67.111.109.109.111.110.47.83.80.95.72.84.84.80.19.47.67.111.109.109.111.110.47.118.109.112.45.115.112.119.115.45.48.51.80

while the pool member name is

19.47.67.111.109.109.111.110.47.118.109.112.45.115.112.119.115.45.48.51.80

Could you please explain what is the logic here?

Thank you,

Best

Olivier