Dell S4048-ON, Руководство по настройке

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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)
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