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Any problem with multicast traffic between Oracle RAC database servers can cause network heartbit problems between servers. In this case you need to see the MULTICAST information for the corresponding interface as below.
1 2 3 4 | -bash-4.3# ifconfig en9 en9: flags=1e084863,c0<UP,BROADCAST,NOTRAILERS,RUNNING,SIMPLEX,MULTICAST,GROUPRT,64BIT,CHECKSUM_OFFLOAD(ACTIVE),LARGESEND,CHAIN> inet 192.168.10.2 netmask 0xffffff00 broadcast 192.160.10.255 tcp_sendspace 131072 tcp_recvspace 65536 rfc1323 0 |
If Multicast exists ad you think there is still a problem, you can test the Multicast as follows.
Download the file mcasttest.tgz that is specified in the Oracle Support document 1212703.1. Extract to any directory and run with the relevant node and interface information.
After downloading, extract the files as follows.
1 2 | -bash-4.3$ gunzip mcasttest.tgz -bash-4.3$ tar xvf mcasttest.tar |
Then go to the mcasttest directory and run it with the node and interface information you want to control. In the example below, nodes are oradb1 and oradb2, interfaces en8 and en9.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 | -bash-4.3$ perl mcasttest.pl -n oradb1,oradb2 -i en8,en9 ########### Setup for node oradb1 ########## Checking node access 'oradb1' Checking node login 'oradb1' Checking/Creating Directory /tmp/mcasttest for binary on node 'oradb1' Distributing mcast2 binary to node 'oradb1' ########### Setup for node oradb2 ########## Checking node access 'oradb2' Checking node login 'oradb2' Checking/Creating Directory /tmp/mcasttest for binary on node 'oradb2' Distributing mcast2 binary to node 'oradb2' ########### testing Multicast on all nodes ########## Test for Multicast address 230.0.1.0 Apr 11 17:37:14 | Multicast Succeeded for en8 using address 230.0.1.0:42000 Apr 11 17:37:15 | Multicast Succeeded for en9 using address 230.0.1.0:42001 Test for Multicast address 224.0.0.251 Apr 11 17:37:16 | Multicast Succeeded for en8 using address 224.0.0.251:42002 Apr 11 17:37:17 | Multicast Succeeded for en9 using address 224.0.0.251:42003 |
