UDP loss problems due to buffers? UDP OVERFLOW !

The tunables for UDP that would modify the socket buffer size include:

* udp_xmit_hiwat - maximum UDP socket datagram in bytes (Default=8192)

* udp_recv_hiwat - maximum UDP socket receive buffer size in bytes (Default=8192)

* udp_max_buf - controls how large send and receive buffers (in bytes) can be for a UDP socket. This should be set to a value higher than the previous tunables, otherwise an error will be returned. (Default=256*1024)

Setting UDP Buffer Limits at kernel level.

ndd -set /dev/udp udp_max_buf 8388608

ndd -set /dev/udp udp_xmit_hiwat


no -o sb_max=8388608 (note: AIX only permits sizes of 1048576, 4194304 or 8388608)

default values:
Solaris udp_max_buf 262144
AIX sb_max 1048576

Detecting UDP Loss(Solaris/AIX)
Solaris:Use netstat -s. Look for udpInOverflows. It will be in the IPv4 part
udpInOverflows = 82427

AIX:Use netstat -s. Look for fragments dropped (dup or out of space) in the ip section.
77070 fragments dropped (dup or out of space).