connecting router to switch

[tolinrome tolinrome]

Hi all,

I'm using packet tracer version 6.0.1 and I need to connect a switch to a router. My goal is to setup a very small LAN. So far I have two 2900 switches and a computer. The computer can ping each interface vlan IP of the layer 2 switches. The two switches are trunked together. Now I need to connect one of those switches to a router and on the other end of the router will be the internet/ISP connection. So these are my questions:

1. Do I trunk the router and switch just like I did the two switches, any recommendations on that?

2. What type of cabling do I use on the router to connect to the internet/ISP?

3. Do I give the outside interface of the router a public IP address?

4. How do I set the default gateway on the router so all the devices can reach it?

5, How do I route the internal traffic that goes to the router to the internet?

Thanks for your help and any suggestions.

[chandra_rc16]

1. Do I trunk the router and switch just like I did the two switches, any recommendations on that?

     Yes you need a trunk connection between switch and the router to support multiple VLAN traffic to reach the router.

2. What type of cabling do I use on the router to connect to the internet/ISP?

     I don't think that PT has this option. (Don't mind if i'm wrong because i never tried it).

3. Do I give the outside interface of the router a public IP address?

     Obviously the outside interface of the router should be a public IP if it is going to connect to ISP.

4. How do I set the default gateway on the router so all the devices can reach it?

     You need to configure sub-interfaces on the router for each VLAN and that sub-interface IP address will be the gateway for all the devices in that particular VLAN. (This is called as Router on-a Stick configuration)

5, How do I route the internal traffic that goes to the router to the internet?

     Once you configure the above steps, since your router is directly connected to the ISP your local devices can access internet.

Please rate if it is helpful for you. And please don't mind if i'm wrong somwheter because i too prapraing for my CCNA with PT.

Regards,

Chandu

[cadet alain · Accepted solution]

Hi,

1) if you have only 1 VLAN then no need for a trunk but if you've got multiple VLANs then you will need a trunk indeed

2)you can simulate with a serial cable or an ethernet cable

3) In real life your WAN interface will have a public IP(routeable on the Internet)

4) if you only have 1 VLAN then just put an IP address on the physical interface connected to your switch, this IP will be in the same subnet as your clients and will be configured as the default gateway for your clients.

Now if you have multiple VLANs then you should configure subinterfaces on the physical interface of the router and assign each subinterface to a particular VLAN with 802.1q and give each an IP address in corresponding subnet( this will be the default gateway for the clients in this vlan)

5) you need a default route pointing towards ISP next-hop or outgoing interface( if it is P2P ).

You will also need to nat from the private subnets ( dynamic PAT) to the WAN interface

Regards

Alain

Don't forget to rate helpful posts.

[tolinrome tolinrome]

I only have 1 vlan on this network but have a couple of switches that I would like to trunk. Users on other vlans from the main office will sometimes connect to it for remote management.

This remote office connects to the main office via site to site vpn where the layer 3 switch is.