Previous logging was very noisy when the agent connection to snmpd
drops:
[ERROR ] agentx.network - run : Empty PDU, connection closed!
[INFO ] agentx.network - disconnect : Disconnecting from localhost:705
[ERROR ] agentx.agent - run : An exception occurred: Empty PDU, disconnecting
[ERROR ] agentx.agent - run : Reconnecting
[INFO ] agentx.agent - run : Opening AgentX connection
[INFO ] agentx.network - connect : Connecting to localhost:705
[ERROR ] agentx.network - connect : Failed to connect to localhost:705
[ERROR ] agentx.agent - run : An exception occurred: Not connected
[ERROR ] agentx.agent - run : Reconnecting
[INFO ] agentx.agent - run : Opening AgentX connection
[INFO ] agentx.network - connect : Connecting to localhost:705
[ERROR ] agentx.network - connect : Failed to connect to localhost:705
[ERROR ] agentx.agent - run : An exception occurred: Not connected
[ERROR ] agentx.agent - run : Reconnecting
Also, reconnects were attempted every 0.1s, but field research shows
that snmpd, if it restarts, takes ~3-5 seconds to come back (note: this
is also due to a systemd delay in restarting it upon failures).
Hammering the connection is not useful.
This change refactors the logging, to avoid redundant messages:
- sleep 1s between attempts (reducing the loop by 10x)
- Either print 'Connected to' or 'Failed to connect to', not both.
- Remove the 'reconnecting' superfluous message
agentx/network.py always turned on debugging. It can be useful to have
debugging logs of the main application without the agentx debug logs, as
they are quite noisy.
Now, ./vpp-snmp-agent.py -d will turn on application debugging but NOT
agentx debugging. ./vpp-snmp-agent.py -d -dd will turn on both.
NOTE: ./vpp-snmp-agent.py -dd will do nothing, because the '-d' flag
determines the global logging level.
