Two routers to one switch

[aroofni]

Hy.

Attached i have my topology. The ports are not active, because i'm working on real life components.

I have 2x cisco 878 routers and a 2950 switch.

And an audiocodecs mp 114 voip gateway.

I configured both routers. One has routing to my wan internet, and when i connect a laptop i have active internet connection.

The problem is, that when i connect a laptop to the second router it doesn't have internet connection. 

Basically it's not pinging. So they can't see each other via switch. 

I was advised to do other connections, because this routing is not really good, but this is my first step, i need to get work with this first, and then complete it with other things. Please help me :)

I wan't to mention that one laptop is for asterisk. It has only a software installed for pbx on virtual machine.

[Julio E. Moisa]

Hi

The router 1 should have a default routing pointing to the ISP router (Internet) also If you are using RIP, it should advertise a default route to Router 2, you can add under RIP the command: default information-originate metric 1. Also I recommend configure RIP with no auto-summary. 

How are you getting Internet access on Router 1, are you using on the hosts the same subnet provided by the ISP, it will work for the local users but unfortunately it is not scalable, I suggest configure NAT in order to provide Internet access to the local and remote users. 

Please let me provide an example config.

Hope it is useful

:-)

[Julio E. Moisa]

Config

Router 1

interface FX/0
ip address <provide by the ISP>
ip nat outside
no shut

interface Fx/1
ip address <internal networks>
ip nat inside   <-- it can be applied to all your internal interface where users are located
no shut

ip access-list standard INTERNAL-NETS
permit 192.168.1.0 0.0.0.255
permit 10.100.100.0 0.0.0.255
<your internal networks to get Internet access>

ip nat inside source list INTERNAL-NET interface Fx/0 overload 

ip route 0.0.0.0 0.0.0.0 <IP next hop, it should be the ISP router> name Internet

router rip
ver 2
no auto-summary
default information-originate metric <1-15>
network <the networks connected to the router, logical or physical>

Router 2

Router rip
ver 2
no auto-summary
network <the networks connected to the router, logical or physical>

It should work on your topology, it can be adjusted to your topology. 

:-)

[aroofni]

Thank you very much. I'm trying it as soon as i'm back to my workstation. :)

[Julio E. Moisa]

Hi

It was a pleasure, please keep me posted.

:-)

[aroofni]

I just realized that all my configs were messed up ( my trunking method and ip allocation was not ok ). So i need to reconfigure each device .  :(

Maybe i should start using only packet tracer, and than physical configuration.

[Julio E. Moisa]

Hi

If you need any assistance, please let me know.

:-)

[aroofni]

Can please attach me a version, of how you would do this configuration in packet tracer ? i would be really really gratefull. i'm trying really hard, i need to get this work :)

i'm ashamed to ask you something like this, but it's my last hope to finally get it done. If not takes you a lot time, please help me.  : )

thank you really

[Julio E. Moisa]

Hi

Sure no problem, I will be sharing the file with you. 

[Julio E. Moisa]

Hi

Attached you will find the packet tracer file, I have included the subnets on the diagram, please note I have used the IP 200.1.1.1 to simulate the NAT, I recommend use debug ip nat  in order to see how it is translated once you are making ping from a computer to the ip 8.8.8.8

The telephony section was not completed because unfortunately my collaboration knowledge is limited. 

Hope it is useful

:-)

[aroofni]

thank you : )

it looks really helpfull. i guess i can move forward with this.

thank you again : )

[Julio E. Moisa]

You are welcome, it was a pleasure my friend.

Have a great day

:-)

[aroofni]

hy :)

Here's another smart question from me : D

why i can't use the switchport trunk command in packet tracer, and on the reallife router i can? (cisco 878) ?

thank you again.

have a nice day

[Julio E. Moisa · Accepted solution]

Hi my friend,

Well, it depends of the switch model, some devices you need to indicate first the dot1q protocol so you need to follow this sequence

interface f1/48
switchport
switchport trunk encapsulation dot1q
switchport mode trunk

Other switch models like 3850 have the dot1q implicity so you dont need the switchport trunk encapsulation dot1q

If Im not wrong, the model 878 is a router, if it has ether switchports you need to configure first the command: switchport, example:

interface f0/1
switchport
switchport mode trunk

it could have implicity the dot1q.

Hope it is useful

:-)

[aroofni]

Helo again : )

I'm started to configure my cisco router's, but i have some problems again.

i can't configure them vithout a vlan interface.

how can i set up a vlan on my topology? i don't cave anything but the two roouters connected to my switch. What should i do ? how can i ad vlan's to my ports? the problem is: i need a dhcp server too, but i can't do anything about it.

My configuration is a complete mess so am i :(

Thank you again. I hope i don't bothered you too much. : - )

have a nice day.