Configure A Route Map For Route Tagging; Continue Clause; Ip Fragment Handling - Dell S4048–ON Configuration Manual

S-series 10gbe switches
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redistribute static metric 20 metric-type 2 tag 0 route-map staticospf
!
route-map staticospf permit 10
match interface TenGigabitEthernet 1/1
match metric 255
set level backbone

Configure a Route Map for Route Tagging

One method for identifying routes from different routing protocols is to assign a tag to routes from that protocol.
As the route enters a different routing domain, it is tagged. The tag is passed along with the route as it passes through different
routing protocols. You can use this tag when the route leaves a routing domain to redistribute those routes again. In the following
example, the redistribute ospf command with a route map is used in ROUTER RIP mode to apply a tag of 34 to all internal
OSPF routes that are redistributed into RIP.
Example of the redistribute Command Using a Route Tag
!
router rip
redistribute ospf 34 metric 1 route-map torip
!
route-map torip permit 10
match route-type internal
set tag 34
!

Continue Clause

Normally, when a match is found, set clauses are executed, and the packet is then forwarded; no more route-map modules are
processed.
If you configure the continue command at the end of a module, the next module (or a specified module) is processed even after a
match is found. The following example shows a continue clause at the end of a route-map module. In this example, if a match is
found in the route-map "test" module 10, module 30 is processed.
NOTE: If you configure the continue clause without specifying a module, the next sequential module is processed.
Example of Using the continue Clause in a Route Map
!
route-map test permit 10
match commu comm-list1
set community 1:1 1:2 1:3
set as-path prepend 1 2 3 4 5
continue 30!

IP Fragment Handling

Dell Networking OS supports a configurable option to explicitly deny IP fragmented packets, particularly second and subsequent
packets.
It extends the existing ACL command syntax with the fragments keyword for all Layer 3 rules applicable to all Layer protocols
(permit/deny ip/tcp/udp/icmp).
Both standard and extended ACLs support IP fragments.
Second and subsequent fragments are allowed because a Layer 4 rule cannot be applied to these fragments. If the packet is to
be denied eventually, the first fragment would be denied and hence the packet as a whole cannot be reassembled.
Implementing the required rules uses a significant number of CAM entries per TCP/UDP entry.
For IP ACL, Dell Networking OS always applies implicit deny. You do not have to configure it.
For IP ACL, Dell Networking OS applies implicit permit for second and subsequent fragment just prior to the implicit deny.
If you configure an explicit deny, the second and subsequent fragments do not hit the implicit permit rule for fragments.
Access Control Lists (ACLs)
119

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