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New Member

Simple SVI / Routed Interface scenario does not work

Hi everybody,

 I tried to setup a simple L2/L3 routing environment with switch and router, just for learning purpose. Please see attached screenshot for the topology. It does not work, I cannot figure out why. Both PC can ping each other and can ping L3-port on switch(192.168.0.1). From switch I can ping everything and from router as well. But what I cannot ping is from PC to routers IP addresses. I would expect to be able to ping both of them. What's wrong?

 Thanks for anyone to have a look at that,

Stefano

 Excerpts from the configs:

 ---------------------------

Config on Switch 3650:

 ip routing

!

interface GigabitEthernet1/0/1

 switchport access vlan 10

!

interface GigabitEthernet1/0/2

 switchport access vlan 20

!

!

interface GigabitEthernet1/0/24

 no switchport

 ip address 192.168.0.1 255.255.255.248

!

interface Vlan10

 ip address 10.1.1.1 255.0.0.0

!

interface Vlan20

 ip address 10.2.2.1 255.0.0.0

!

ip route 0.0.0.0 0.0.0.0 GigabitEthernet1/0/24

 ---------------------------

Config on Router 2911:

 interface GigabitEthernet0/0

 ip address 192.168.0.2 255.255.255.248

!

interface GigabitEthernet0/1

 ip address 99.0.0.1 255.0.0.0

!

interface GigabitEthernet0/2

 no ip address

 shutdown

!

ip route 0.0.0.0 0.0.0.0 99.0.0.2

1 ACCEPTED SOLUTION

Accepted Solutions

Re: Simple SVI / Routed Interface scenario does not work

Hi,

PCs are in 10.x.x.x/8 network.
Switch (3650) is configured as a router ("IP routing" enabled).
Router (2911) is connected on one side with the switch on 192.168.0.2/29 network.

PC <--> SW (Layer 3 SW) <--> Router.

You can not ping from PCs to the 2911 router. The reason is there is no route from the router back to the PCs in the router RIB (run "show ip route"). You can simply fix this by adding a static route in the router:
ip route 10.1.1.0 255.0.0.0 192.168.0.1
ip route 10.2.2.0 255.0.0.0 192.168.0.1

HTH,
Meheretab
3 REPLIES

Re: Simple SVI / Routed Interface scenario does not work

Hi,

PCs are in 10.x.x.x/8 network.
Switch (3650) is configured as a router ("IP routing" enabled).
Router (2911) is connected on one side with the switch on 192.168.0.2/29 network.

PC <--> SW (Layer 3 SW) <--> Router.

You can not ping from PCs to the 2911 router. The reason is there is no route from the router back to the PCs in the router RIB (run "show ip route"). You can simply fix this by adding a static route in the router:
ip route 10.1.1.0 255.0.0.0 192.168.0.1
ip route 10.2.2.0 255.0.0.0 192.168.0.1

HTH,
Meheretab

Re: Simple SVI / Routed Interface scenario does not work

Route on 2911 is missing (as meheretabm said, but just one route is missing)

 

ip route 10.0.0.0 255.0.0.0 192.168.0.1

 

However:

interface Vlan10
 ip address 10.1.1.1 255.0.0.0
!
interface Vlan20
 ip address 10.2.2.1 255.0.0.0

 

Should not be allowed on device (at least with both interfaces active) since network IP address ranges overlap.

 

New Member

Re: Simple SVI / Routed Interface scenario does not work

Hi Meheretab, hi Predrag,

 

thanks to both of you. Backwards routes where missing, now it works. And yes, the subnet mask for SVI addresses was wrong in my posting, on the switch it was correct (255.255.255.0).

 

Sorry for creating efforts, should have seen that myself.

 

Regards, Stefano

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