White Papers

CoPP
Control Plane Policing (CoPP) in Dell EMC Networking OS provides a method for protecting CPU bound control plane packets by policing
packets punted to CPU with a specied rate and from undesired or malicious trac.
CoPP is implemented using:
• Rate shapers in CPU port scheduling nodes for queue based shaping
• Rate limiters in egress ACL for protocol based limiting
• Protocol to queue mapping
• Conguring CPU queue length
The user will need to congure the boot-type to warmboot under the reload-type conguration mode. Warmboot is a system reload
technique where the NPU will not restart. Only the CPU is restarted to bring up the upgraded software. Software upgrade ISSU, is the
typical use case for warmboot. Since BCM chip is already up and running while the software is restarted, there should not be any trac
outage during warmboot. However, since the CPU is restarted during the warmboot process, control plane trac drop will be observed and
the same would resume post warmboot.
Mirroring ow control packets
ISSU for mirroring ow control packets is a graceful implementation . The mirror ACL FP rules and the MTPs would be cleared out when
the box comes up in warmboot during the ISSU audit phase, and the ows are re-programmed again with mirror action when the mirroring
congurations are downloaded. In case of legacy L3 ACL based mirroring , the mirroring actions would be cleared out and re-programmed
while the FP rules are retained.
PFC
This feature has been designed to ensure that there is no trac loss with respect to PFC during warmboot or upgrade to a dierent switch
image.
The user will need to congure the boot-type to warmboot under the reload-type conguration mode. All the supported feature information
gets stored in a persistent storage, and when the switch goes in for a reload, all hardware programmed entries will be saved and trac will
be treated seamlessly, during reload. After the reload is complete, the running-cong and startup-cong will be compared and if there is a
dierence, the device will be programmed based on the startup-cong.
QoS
This feature has been designed to ensure that there is no trac loss with respect to QoS trac during warmboot or upgrade to a dierent
switch image.
The user will need to congure the boot-type to warmboot under the reload-type conguration mode. All the supported feature information
gets stored in a persistent storage, and when the switch goes in for a reload, all hardware programmed entries will be saved and trac will
be treated seamlessly, during reload. After the reload is complete, the running-cong and startup-cong will be compared and if there is a
dierence, the device will be programmed based on the startup-cong.
Tunnel Conguration
This feature has been designed to ensure that there is no trac loss with respect to tunneled trac during warmboot or upgrade to a
dierent switch image.
The user will need to congure the boot-type to warmboot under the reload-type conguration mode. All the supported feature information
gets stored in a persistent storage, and when the switch goes in for a reload, all hardware programmed entries in CAM and FIB will be saved
and trac will be treated seamlessly, during reload. After the reload is complete, the running-cong and startup-cong will be compared
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In-Service Software Upgrade