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+Intro:
+------
+This is an SNMP-based fencing agent for RHCS.  It was designed with the use-case
+of disabling ethernet ports on an iSCSI SAN, but could be used to disable any
+port on any SNMP v1/2c/3 device that implementes the IF-MIB.
+
+The script requires NetSNMP to be installed and working on all nodes
+in the cluster.  There are no requirements for any MIBs to be setup --- all of
+the required OIDs are hard-coded into the script.  Since the IF-MIB is an IETF
+standard, these identifiers are very widely supported and will not change.
+
+
+Typical usage:
+--------------
+To use this agent with the switch used on the iSCSI network, you'll need:
+   1) A managed switch running SNMP.
+   2) An SNMP community with write privileges.
+   3) Permission to send SNMP through any ACLs or firewalls from the nodes.
+   4) The ifIndex or ifPort associated with the ports being used by the cluster nodes.
+
+Consider a three-node cluster composed of A, B, and C.  Each node has two
+network interfaces - one used for network and cluster communication, the second
+used for iSCSI traffic.  If A needs to be fenced, B and C will run this script
+to administratively disable the switchport for A's connection to the iSCSI
+storage.
+
+If you are using a single interface for cluster and iSCSI traffic, this will
+still work, but you will lose network connectivity to the fenced host.
+
+
+cluster.conf:
+-------------
+There is no GUI support for this fence agent at this time.  To use it, you will
+need something like this cluster.conf
+
+<fencedevice agent="fence_ifmib" name="myswitch" comm="fencing" ipaddr="sw1"/>
+
+In a node's fencing methods, you'll include a line like this:
+
+<device name="myswitch" port="43" option="off"/>
+
+This node will be fenced by disabling the port with ifIndex 43 on the host sw1.
+In SNMP speak, we set IF-MIB::ifAdminStatus.43 = down(2).
+
+If you will use port name (like fc1/1), script will try to find ifIndex.