TCP/IP problems with snmpd response to queries

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If snmpd is not responding to queries and there are no log messages received, the packet might be to large for the kernel User Datagram Protocol (UDP) packet handler.

If this is the case, increase the kernel variables, udp_sendspace and udp_recvspace by issuing the following commands:

no -o udp_sendspace=64000
no -o udp_recvspace=64000

The maximum size for a UDP packet is 64K. If your query is larger than 64K, it will be rejected. Split the packet into smaller packets to avoid this problem.