Configuring the Encapsulated Remote Port MirroringThe ERPM session copies traffic from the source ports/lags or source VLANs and forwards the traffic using routable GRE-encapsulated packets to the destination ip address specified in the session.Important:The steps to be followed for the ERPM Encapsulation :• Dell Networking OS supports ERPM Source session only. The Encapsulated packets terminate at the destination ip or atthe analyzer.• Make sure that the destination ip is reachable via the configured ip route (static or dynamic)• The system MTU should be configured properly to accommodate the increased size of the ERPM mirrored packet.• The system encapsulates the complete ingress or egress data under GRE header, IP header and outer MAC header andsends it out at the next hop interface as pointed by the routing table.• The source IP address can be any port's ip address defined in the box but it should be unique and should not be assigned toany other system in the network.• The keyword ‘flow-based enable’ should have been specified in case of source as vlan or where monitoring on a per flowbasis is desired.• The keyword monitor should have been specified in the access list rules for which we need to mirror.• The maximum number of source ports that can be defined in a session is 128.• The system allows to configure upto 4 ERPM sessions.• ERPM sessions do not copy locally sourced Remote-VLAN traffic from source trunk ports that carry RPM VLANs. ERPMsessions do not copy locally sourced ERPM GRE-encapsulated traffic from source ports.• Source Vlan monitoring can be done only for ingress packets and is not supported for egress direction.Changes to Default Behavior• Rate-limiting ïs no longer done for ERSPAN traffic.• Same port can be configured as both source and destination in an ERSPAN session.• TTL and ToS values can be configured in IP header of ERSPAN traffic.Configuration steps for ERPMERPM sample steps for configuring the Source sessionsStep Command Purpose1 configure terminal Enter global configuration mode.2 monitor session type erpm The needs to be unique and not already definedin the box specifying type as 'erpm' defines a RPMsession.3 source Interface | Range Specify the port or list of ports that needs to bemonitored4 direction Specify rx, tx or both in case to monitor ingress/egress or both ingress and egress packets on thespecified port..5 erpm source-ip dest-ip Specify the source ip address and the destination ipwhere the packet needs to be sent.6 flow-based enable Specify flow-based enable for mirroring on a flow byflow basis and also for vlan as source.Port Monitoring 555
