Error Message

Error observed from Oracle logs
gc cr block lost
wait for scn ack
gc cr block congested

The 'Rcv out of window' data packets increased because   they arrived either before an expected ACKnowledge of a lesser sequence number than the data packet, or after an ACKnowledge with a greater sequence number.By design, every LLT packet has a sequence number and there is the notion of "the" current sequence number (i.e. the next one we expect). If the received packet seqno is less than that OR if the received pkt seqno is greater than (expected + window), we reject the packet and increment the "Rcv out of window" counter.

Note that the number of "Rcv out of window" is less than 1% of "rcv data packet". So this is no concern. These might be packets which came twice to LLT. Are switches being used or hubs? Switches can sometimes send duplicate data.

Applies To

Solaris 10 running Oracle RAC 5.0MP1