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How does a prefix list work?
Prefix lists work very similarly to access lists; a prefix list contains one or more ordered entries which are processed sequentially. These accomplish the same tasks as the two access list entries in the earlier example: deny 10.0. 0.0/24 denies the exact prefix 10.0. 0.0/24, and permit 0.0.
What is Cisco distribute list?
A distribute-list is used to control routing updates either coming TO your router or leaving FROM your router. Distribute-lists work on a variety of different IOS routing protocols. Because of that, learning how to use distribute-lists is very valuable.
How do I create a route map on my Cisco router?
Here are some examples of set commands:
- Change the BGP AS path length.
- Set a BGP community.
- Set the BGP weight.
- Set the metric of an OSPF or EIGRP route in redistribution.
- Set a redistribution tag.
- Set the next hop IP address in policy-based routing.
- Set the DSCP value of an IP packet.
- And many other options…
How do you set up a distribute list?
Go to the configuration of the EIGRP process and use the distribute-list command to see your options. As you can see we can choose between an access-list, a prefix-list or a route-map. Let’s start with the access-list. You are probably familiar with the concept of access-lists if you studied CCNA.
Can a prefix list match an access list?
Prefix lists cannot. Extended/Standard ACL’s can use wildcard masks which allow for the specification of arbitrary addresses or ranges of addresses. Prefix lists can’t do this. Prefix lists can match on prefix lengths – either minimum or maximum lengths with the “ge” and “le” keywords, respectively.
What’s the difference between an ACL and a prefix list?
In addition to what John Jensen said, I would add that ACLs are also used for security purposes (e.g. limiting remote access) while prefix-list cannot have this function by their own. Prefix-lists stick to L3, while ACL may go one layer up, bringing additional functionality.
How to call an access list in distribute?
Distribute can call a access-list or a prefix-list. You need to use keyword prefix and then specify the number or name of the prefix-list. 2. Offset-list:
How is the prefix list used in routing?
Prefix-list is used for route-filtering and route redistribution because it matches on prefixes either sent,received or present in the routing table or BGP table. They match on bits in the prefix but also on the prefix-length.