[DNSDIST] snmp agentx stops working after snmp service restart

[rodehoed]

• Program: dnsdist
• Issue type: Bug report

Short description

When starting up dnsdist and snmpd is running you will see that dnsdist is connected to the Agentx and snmpwalk returns proper values. But when the snmp service is restarted things get lost and it won't return any results.

Environment

• Operating system: el6
• Software version: 0.0.1560g9d084b6 (master/may 15th)
• Software source: pdns official repo

Steps to reproduce

1. Have SNMP with agentx configuration running and start dnsdist
2. snmpwalk -v2c -c 'community' host DNSDIST-MIB::latency01: SUCCESS
3. restart snmp service
4. snmpwalk -v2c -c 'community' host DNSDIST-MIB::latency01: FAILS: o Such Object available on this agent at this OID
5. restart dnsdist, makes it working again

Expected behaviour

DNSDIST-MIB::latency01.0 = Counter64: 0

Actual behaviour

DNSDIST-MIB::latency01 = No Such Object available on this agent at this OID

Other information

Socket:
ls -al /var/agentx/master srwx------. 1 dnsdist dnsdist 0 May 16 13:44 /var/agentx/master
dnsdist config line:

snmpAgent(true,"/var/agentx/master")
My guess is that dnsdist is not reconnecting to socket after it has been terminated?

Usecase

Want to get nice graphs :-)