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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.
NOTE:
When configuring ERPM, follow these guidelines
● The Dell EMC 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.
● Configure the system MTU to accommodate the increased size of the ERPM mirrored packet.
● The maximum number of source ports you can define 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.
● Specify flow-based enable in case of source as VLAN or where you need monitoring on a per-flow basis.
● Specify the monitor keyword in the access list rules for which you want to mirror.
● The system allows you to configure up to four 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.
● Flow-based mirroring is supported only for source VLAN ingress traffic.
Changes to Default Behavior
● Rate-limiting is supported for the ERSPAN traffic.
● You can configure the same port as both source and destination in an ERSPAN session.
● You can configure TTL and TOS values in the IP header of the ERSPAN traffic.
Configuration steps for ERPM
To configure an ERPM session:
Table 72. 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 the Monitoring-
Session configuration mode. The session number
needs to be unique and not already defined.
3
source { interface | range }
direction {rx | tx | both}
Specify the source port or range of ports. Specify
the ingress (rx), egress (tx), or both ingress and
egress traffic to be monitored. You can enter
multiple source statements in an ERPM monitoring
session
4
erpm source-ip <id> dest-ip <id>
gre-protocol <value>
Specify the source IP address, destination IP
address, and GRE-protocol type value to which
encapsulated mirrored traffic is sent.
5
no flow-based enable
ERPM to be performed on a flow-by-flow basis or
if you configure a VLAN source interface. Enter the
no flow-based command to disable flow-based
ERPM.
6
no disable
Enter the no disable command to enable the ERPM
session.
Port Monitoring 671