Inter-Vlan Routing Configuration

[jessnew321]

I am configuring a Cisco 2960C switch for inter-vlan routing and can't seem to get it working. I have set the gateway of last resort as my routers eth1 interface ip (192.168.1.1) and the vlan shows up in the routing table but I cannot ping from a pc or get any type of vlan routing.

I have a static route set up on the router with a destination of the vlan in question using 192.168.1.1 as its next hop. Obviously something is not configured correctly, so what am I missing??

[Madhukrishnan Gopinathan Nair]

What are the two vlans..have you configured SVI for them in switch? Or are you using Router on Stick where everything going to ur router ?

Share configuration.

Thanks,

Madhu

[jessnew321]

Here are some configurations.

SW1#show vlan br

VLAN Name                             Status    Ports
---- -------------------------------- --------- -------------------------------
1    default                          active    Fa0/1, Fa0/2, Fa0/3, Fa0/4
                                                Fa0/5, Fa0/6, Fa0/7, Gi0/1
                                                Gi0/2
2    Data                             active    
3    Voice                            active    
4    IP-Camera                        active    
5    WiFi                             active    
99   Management                       active    Fa0/8
1002 fddi-default                     act/unsup
1003 token-ring-default               act/unsup
1004 fddinet-default                  act/unsup
1005 trnet-default                    act/unsup

SW1#show ip int br
Interface              IP-Address      OK? Method Status                Protocol
Vlan1                  192.168.1.2     YES NVRAM  up                    up      
Vlan2                  192.168.0.1     YES manual up                    down    
Vlan3                  192.168.3.1     YES manual up                    down    
Vlan4                  192.168.4.1     YES manual up                    down    
Vlan5                  192.168.5.1     YES manual up                    down    
Vlan99                 192.168.99.1    YES manual up                    down    
FastEthernet0/1        unassigned      YES unset  down                  down    
FastEthernet0/2        unassigned      YES unset  up                    up      
FastEthernet0/3        unassigned      YES unset  up                    up      
FastEthernet0/4        unassigned      YES unset  up                    up      
FastEthernet0/5        unassigned      YES unset  down                  down    
FastEthernet0/6        unassigned      YES unset  down                  down    
FastEthernet0/7        unassigned      YES unset  down                  down    
FastEthernet0/8        unassigned      YES unset  down                  down    
GigabitEthernet0/1     unassigned      YES unset  up                    up      
GigabitEthernet0/2     unassigned      YES unset  down                  down  

[Madhukrishnan Gopinathan Nair]

Are you trying to route between vlan 1 and 99?

What are your pc's gatway addresses which are not able to ping each other?

[jessnew321]

I think I've had a breakthrough. I had configured an incorrect default gateway for the pc. In this case the 192.168.99.0 network. After I configured the default gateway to 192.168.99.1 on the pc I was able to connect.

If you could elaborate it would be welcome. I'm still not sure I fully understand the concept. I'm going to check a couple of other things and post my findings.

Thanks

[Madhukrishnan Gopinathan Nair]

When you create 2 SVI (in this case vlan 1 and 99), the switch enables routing between these vlans by default.  If you do a

sh ip route

on switvh you can see these 2 subnets are known to switch over vlan 1 and 99. 

So all you need to do is ensure your pc have right gateway adresses to send packets for remote subnets.

Hope this helps.

******** Please rate all useful posts*******

Thanks,

Madhu

[Martin Carr]

This is incorrect, this would be true for a layer 3 switch, which the 2960 isn't.

To achieve what you are looking for you need to configure ROAS, basically a trunk is configured between the two and then you create a sub interface for each VLAN.

Martin

[jessnew321]

@Martin, unless I'm mistaken, when the 2960C's ios is upgraded to version 15.2.3E1 it is capable of some L3 routing, i.e. it keeps a routing table. I believe static routing only but would have to check on that.

I'm pretty sure I have the router performing inter-vlan routing as I speak. If you check the cisco boards and google there is documentation. It just needs to have the correct ios version.

Can anyone definitively confirm or deny?

[Madhukrishnan Gopinathan Nair]

Share us a 

sh ver

sh ip route

From 2960

Thanks,

Madhu

[jessnew321]

Version is as above, 15.2.3E1. I updated it myself from 12.2, specifically for the (limited) L3 capability.

I will post the output from ip route this evening.

Many thanks.

[jessnew321]

@Madhu, here is the version output (truncated):

SW1#show version
Cisco IOS Software, C2960C Software (C2960c405-UNIVERSALK9-M), Version 15.2(3)E1, RELEASE SOFTWARE (fc3)

and here is the ip route output:

SW1#show ip route
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP
       a - application route
       + - replicated route, % - next hop override

Gateway of last resort is 192.168.1.1 to network 0.0.0.0

S*    0.0.0.0/0 [1/0] via 192.168.1.1
      192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks
C        192.168.1.0/24 is directly connected, Vlan1
L        192.168.1.2/32 is directly connected, Vlan1
      192.168.99.0/24 is variably subnetted, 2 subnets, 2 masks
C        192.168.99.0/24 is directly connected, Vlan99
L        192.168.99.1/32 is directly connected, Vlan99

I do not have a trunk line configured, which I thought was necessary for router-on-a-stick.

[Martin Carr]

With the right software it can perform basic L3 functionality, which is limited to 16 static routes, it cannot perform inter-vlan routing.

Martin

[jessnew321]

It may just be semantics but when a host in one vlan can communicate (ping) with a host in another vlan...that is inter-vlan routing, however basic it may be. At least that's how Cisco defines the term.

It will not do routing protocols and it is limited to 16 static routes, so that is correct but router-on-a-stick is not necessary with this particular switch and ios version.

[Martin Carr]

You said you have a router, so this is would do the routing, thats why I said you need to configure ROAS. (in which case you wouldn't need L3 functionality on the switch)

At the moment you have one active SVI, i.e. VLAN 1. This historically was the case with this switch, hence why I didn't think it would be possible. However, I have had a look and it appears this has been changed, so thats the first thing to look at.

Martin

[jessnew321]

Apologies Martin. Interface vlan 99 was down because I didn't have anything attached to it at that time. I really should have had it up before I posted.

Thanks for your contributions and insights too. It is very much appreciated.