"match interface null0" means that any routes that have null0 as next hop interface are to be matched. The corresponding clause (number 10) has a deny, so matching routes will not be redistributed. In short, routes with a next-hop of null0 are not redistributed.
The next clause (number 20) has a permit and no match criteria, so all other routes are matched and redistributed.
In conclusion, with this map all routes are redistributed, except those that have a next-hop of null0.
Routes with a next-hop of null0 can be configured for example via static route configuration (could be also EIGRP summary routes). What kind of (routing protocol) routes are redistributed into which routing protocol? Are you redistributing lets say static into OSPF?
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...
Attached policy provides CLI access to the Cisco 4G router over text messaging. Two files are in the attached .tar file:
2. PDF with instructions on how to load and use the .tcl file.