Service Manual

Table Of Contents
Encapsulated Remote Port Monitoring
Encapsulated Remote Port Monitoring (ERPM) copies traffic from source ports/port-channels or source
VLANs and forwards the traffic using routable GRE-encapsulated packets to the destination IP address
specified in the session.
Important:
When configuring ERPM, follow these guidelines
The Dell Networking OS supports ERPM source session only. Encapsulated packets terminate at
the destination IP address or at the analyzer.
You can configure up to four ERPM source sessions on switch.
The system MTU should be configured properly to accommodate the increased size of the
ERPM mirrored packet.
The maximum number of source ports that can be defined in a session is 128.
The system encapsulates the complete ingress or egress data under GRE header, IP header and
outer MAC header and sends it out at the next hop interface as pointed by the routing table.
The keyword ‘flow-based enable’ should have been specified in case of source as vlan or where
monitoring on a per flow basis 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. ERPM sessions 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.
A flow-based source VLAN can be monitored only for ingress traffic (not egress traffic).
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 ERPM
To configure an ERPM session:
Table 66. Configuration steps for ERPM
Step Command Purpose
1 configure terminal
Enter global configuration mode.
2
monitor session <id> type erpm Specify a session ID and ERPM as the type
of monitoring session, and enter
Monitoring-Session configuration mode.
Port Monitoring
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