Dell S4820T, Configuration Manual

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Non-contiguous bitmasks for PBR allows more granular and flexible control over routing policies. You
can include or exclude addresses that are in the middle of a subnet. You can enter bitmasks using the
dotted decimal format.
Dell#show ip redirect-list
IP redirect-list rcl0:
Defined as:
seq 5 permit ip 200.200.200.200 200.200.200.200 199.199.199.199
199.199.199.199
seq 10 redirect 1.1.1.2 tcp 234.224.234.234 255.234.234.234
222.222.222.222/24
seq 40 ack, Next-hop reachable(via Te 8/1)
Applied interfaces:
Te 8/2
Hot-Lock PBR
Ingress and egress Hot Lock PBR allows you to add or delete new rules into an existing policy (already
written into content address memory [CAM]) without disruption to traffic flow. Existing entries in CAM are
adjusted to accommodate the new entries. Hot Lock PBR is enabled by default.
Configuration Task List for Policy-based Routing
To enable the PBR:
• Create a Redirect List
• Create a Rule for a Redirect-list
• Create a Track-id list. For complete tracking information, refer to Object Tracking chapter.
• Apply a Redirect-list to an Interface using a Redirect-group
PBR Exceptions (Permit)
To create an exception to a redirect list, use the
permit
command. Use exceptions when a forwarding
decision is based on the routing table rather than a routing policy.
Dell Networking OS assigns the first available sequence number to a rule configured without a sequence
number and inserts the rule into the PBR CAM region next to the existing entries. Because the order of
rules is important, ensure that you configure any necessary sequence numbers.
The
permit
command is never applied because the redirect list covers all source and destination IP
addresses.
The following example shows an ineffective PBR Exception due to Low Sequence Number.
ip redirect-list rcl0
seq 5 redirect 2.2.2.2 ip any any
seq 10 permit ip host 3.3.3.3 any
To ensure that the
permit
command or PBR exception is effective, use a lower sequence number, as
shown:
ip redirect-list rcl0
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Policy-based Routing (PBR)