Implementing Policy-Based Routing With Dell Networking Os - Dell S4820T Configuration Manual

To enable a PBR, create a redirect list. Redirect lists are defined by rules, or routing policies. You can
define following parameters in routing policies or rules:
• IP address of the forwarding router (next-hop IP address)
• Protocol as defined in the header
• Source IP address and mask
• Destination IP address and mask
• Source port
• Destination port
• TCP Flags
After a redirect-list is applied to an interface, all traffic passing through it is subjected to the rules defined
in the redirect-list.
The traffic is forwarded based on the following:
• Next-hop addresses are verified. If the specified next hop is reachable, the traffic is forwarded to the
specified next-hop.
• If the specified next-hops are not reachable, the normal routing table is used to forward the traffic.
• Dell Networking OS supports multiple next-hop entries in the redirect lists.
• Redirect-lists are applied at Ingress.
PBR with Redirect-to-Tunnel Option:
The user can provide a tunnel id for a redirect rule. In this case, the resolved next hop would be the
tunnel interface IP. The qualifiers of the rule would be pertaining to the inner IP details. For next hop to be
a tunnel interface user needs to provide tunnel id mandatory. Instead if user provides the tunnel
destination IP as next hop, that would be treated as IPv4 next hop and not tunnel next hop.
PBR with Multiple Tacking Option:
Policy based routing with multiple tracking option extends and introduces the capabilities of object
tracking to verify the next hop IP address before forwarding the traffic to the next hop. The verification
method is made transparent to the user. The multiple tracking options feature is most suitable for routers
which have multiple devices as the next hop (primarily indirect next-hops and/or Tunnel Interfaces in this
case). It allows you to backup Indirect Next-hop with another, choose the specific Indirect Next-hop
and/or Tunnel Interface which is available by sending ICMP pings to verify reach ability and/or check the
Tunnel Interface UP or DOWN status, and then route traffic out to that next-hop and/or Tunnel Interface
Implementing Policy-based Routing with Dell
Networking OS
• Non-contiguous bitmasks for PBR
• Hot-Lock PBR
Non-Contiguous Bitmasks for PBR
Policy-based Routing (PBR)
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