Znyx Networks bh5700 manual Zgmrpd, Std 802.1D, 1998 Edition

zgmrpd

NAME

zgmrpd - GARP Multicast Registration Protocol (GMRP) daemon for the OpenArchitect switch. (Partially supported in this release.)

SYNOPSIS

zgmrpd [-d <level>] [-f] [-h <hostname>] [-p <ppa>] [-t <target>]

DESCRIPTION

zgmrpd is run after the network interfaces are created and initialized with zconfig, and started with ifconfig(1M).zgmrpd starts a background task that implements the GARP Multicast Registration Protocol (GMRP) protocol for a specified interface, either a zhp or bzhp. GMRP provides a Layer-2 mechanism for determining which ports in a VLAN are listening to which multicast addresses. zgmrpd updates the multicast table in silicon with this information, so that the multicast traffic is forwarded only to the ports in a VLAN to which listening hosts are attached. This optimizes packet flow through the switch. The background task started by zgmrpd continues throughout the life of the Layer 2 network. GMRP is specified in ANSI/IEEE

Std 802.1D, 1998 Edition.

zgmrpd manages the switch multicast table (MARL). Based on GMRP packets received on the target interface, zgmrpd creates, updates, or deletes an entry in the MARL. The key to each MARL entry is a source Ethernet multicast address combined with a VLAN ID. Two port bitmaps are maintained: one that identifies the untagged members of the VLAN, and one which identifies which ports of the VLAN have listening hosts attached.

NOTE: OpenArchitect does not tag BPDU packets. This means that if a port belongs to multiple VLANs, exactly which Multicast MAC/VLAN entry to create, modify, or delete cannot be determined. GMRP should not be used when ports belong to multiple VLANs. If the target is a zhp, it’s recommended that the zhp contain all the ports on the switch.

When the maximum number of entries in the MARL is reached, zgmrpd deletes a random entry prior to adding the next entry.

By default, while GMRP is running, unregistered multicast traffic is filtered on the target interface. The GMRP protocol provides a mechanism for changing the filtering behavior on a per- port basis. Filtering behavior can be set to filter unregistered multicast traffic, forward unregistered multicast traffic, or forward all traffic. zconfig can be used to set the filtering mode of each port. See zconfig . Ports connected to routers should be set to “Forward All” filtering mode manually with zconfig after zgmrpd is up and running. When zgmrpd is terminated, filtering behavior is set to forward unregistered multicast traffic on each port in the target interface.

Ethernet Switch Blade User's Guide release 3.2.2j page 295