How can I query a node, via SNMP, to gain the cluster IP address?

Here is the scenario:

ISILON Cluster has cluster address of X.X.X.100 and 3 nodes with addresses X.X.X.101, X.X.X.102 and X.X.X.103.  If I walk any node -  I get the following output and you can see that the X.X.X.100 cluster address in the SNMP output.

But I can't figure out how to query directly for it -instead of doing the entire snmpwalk:

$ snmpwalk -v 2c -c XXXXX -Ln -m ISILON-MIB X.X.X.101

SNMPv2-SMI::mib-2.1.1.0 = STRING: "Isilon OneFS C-1 v7.0.2.4 Isilon OneFS v7.0.2.4 B_7_0_2_184(RELEASE) amd64"

SNMPv2-SMI::mib-2.1.2.0 = OID: ISILON-MIB::cluster

SNMPv2-SMI::mib-2.1.3.0 = Timeticks: (1332886052) 154 days, 6:27:40.52

SNMPv2-SMI::mib-2.1.4.0 = STRING:

SNMPv2-SMI::mib-2.1.5.0 = STRING: "isilon-c-1"

SNMPv2-SMI::mib-2.1.6.0 = STRING: "XXXX"

SNMPv2-SMI::mib-2.1.7.0 = INTEGER: 12

SNMPv2-SMI::mib-2.1.8.0 = Timeticks: (19) 0:00:00.19

SNMPv2-SMI::mib-2.1.9.1.2.1 = OID: SNMPv2-SMI::snmpModules.10.3.1.1

SNMPv2-SMI::mib-2.1.9.1.2.2 = OID: SNMPv2-SMI::snmpModules.11.3.1.1

SNMPv2-SMI::mib-2.1.9.1.2.3 = OID: SNMPv2-SMI::snmpModules.15.2.1.1

<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>

SNMPv2-SMI::mib-2.4.20.1.1.X.X.X.100 = IpAddress: X.X.X.100

SNMPv2-SMI::mib-2.4.20.1.1.X.X.X.101 = IpAddress: X.X.X.101