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justinlim
Posts: 2
Registered: ‎03-19-2010
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Question on Next-hop in Routing Table

Hi peeps, I have a question regarding the next-hop address as shown from the extracts below :

 

user@host> show route protocol static
inet.0: 12 destinations, 12 routes (12 active, 0 holddown, 0 hidden) + = Active Route, - = Last Active, * = Both


192.168.2.128/27 *[Static/5] 00:03:13
> to 172.20.106.10 via fe-0/0/5.106
192.168.2.192/26 *[Static/5] 00:03:13
> to 10.210.14.131 via ge-0/0/0.0
192.168.2.192/27 *[Static/5] 00:03:13
> to 172.18.1.1 via ge-0/0/1.0
192.168.2.224/28 *[Static/5] 00:01:06
> to 10.210.14.130 via ge-0/0/0.0

 

What will be the next-hop IP address used for the destination IP address of 192.168.2.239? (Assume the only routes to this destination are static routes.) Also, kindly explain to me if the interface logical unit plays any role on it.

 

Thanks in advance!

Super Contributor
B2
Posts: 211
Registered: ‎05-06-2010
0

Re: Question on Next-hop in Routing Table

It looks like 10.210.14.130 will be chosen.  I'm not quite sure what you mean when you ask whether the interface logical unit plays any role in it...it shouldn't play any role in the actual route selection, but it should play some role in how the router actually reaches the next hop.

Visitor
justinlim
Posts: 2
Registered: ‎03-19-2010
0

Re: Question on Next-hop in Routing Table

Yes it is very weird given the fact that I went through some dumps and the answer would be to 172.18.1.1 via ge-0/0/1.0.

 

I know it sounds crazy and all because even the subnet mask doesn't fit correctly into it! But what's crazier was, 3 out of 3 dumps i've got my hands on, all gave the same answer.

 

Thus, i was wondering if the interface ge-0/0/0.0 has some special roles on it and is not usable as a next-hop.

Distinguished Expert
aarseniev
Posts: 1,722
Registered: ‎08-21-2009
0

Re: Question on Next-hop in Routing Table

Hello,

 

This route

 

 

192.168.2.192/27 *[Static/5] 00:03:13
> to 172.18.1.1 via ge-0/0/1.0

 

 

-- cannot possibly match dst.IP == 192.168.2.239 because 192.168.2.192/27 only covers destinations from 192.168.2.192  to 192.168.2.223.

So the dumps You used were incorrect.

HTH

Regards

Alex

 

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Super Contributor
B2
Posts: 211
Registered: ‎05-06-2010
0

Re: Question on Next-hop in Routing Table

Yeah, there seems to bea  piece missing here.  What is the output of 'show route 192.168.2.239 detail' ?

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