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Suppose having an routing table in which the default-route is missing can a router work without a default-route or the table is incomplete?

and having these two entries is also legit or there is an overlap problem for the network addresses?

Type        Network            Next Hop
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Did you mean /29 in the second line? – mulaz Feb 4 '13 at 17:11
No it's 28 and I'm asking because if it's YES on my both questions then there the second address is not an valid network address. – Lucian Enache Feb 4 '13 at 17:12
1 it's not a valid route. or are. - – mulaz Feb 4 '13 at 17:14
Thanks You've answered my problem – Lucian Enache Feb 4 '13 at 17:19
up vote 3 down vote accepted

For the first question, the answer is 'yes'. The router will work, but only the networks in the routing table will be accessible. For everything else, you'll get a "destination host unreachable".

For the second, if you have two (or more) overlaping networks, the longest-prefix-match will be used. So, if you want to access, the second route will be used (doesn't matter in your case, since both use the same gateway), because the the match is longer (more bits match the network ID/mask).

If you have: via gw1 via gw2 via gw3 via gw4

and want to ping, the packet will go via gw4, since it matches more bits with the network id/mask then other routes.


is not a valid route (if you use /28, is a network ID). However is a valid route.

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thanks, still is it possible for the second address to get an error because that is not an valid network address ? – Lucian Enache Feb 4 '13 at 17:09

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