Re: Router, Switch, Satelite Modem Cabling Issue

jasonobrown · ‎07-13-2011

I have a 2621 xm router and a Catalyst 3500 Series XL switch. They haven't been used for a couple of years, but the configurations worked then and haven't been changed. I just got them out of storage and I'm trying set them back up. The problem I'm having is that I cannot get a connection from the router to my modem. I've attached the config files so you can see what's going on, but here's a quick run down. I'm positive that switchport 48 connects to the router on fa0/0 because that's the only way dhcp works. That is the only thing I know for sure though. I have a hunch that the modem was going into the switch possibly on port 47, and then into router fa1/0 from another port on the switch. I also had a linksys wireless access point coming off of the switch and think it was on port 46. If anyone can figure this out please let me know. I suffered a brain injury a while back and my memory isn't what it used to be.

Gerald Vogt · ‎07-13-2011

From the config it seems as if you have recovered well from your brain injury.

Only port Fa0/0 is used on the router. It's tagged. The configuration on the router Fa0/0 matches the configuration on the switch port Fa0/48.

VLAN 50 seems to be the outside VLAN which connects to the internet. This suggests that Fa0/47 on the switch connects to the modem.

VLAN 300 is labeled "Wireless" and seems to be connected on switch port Fa0/46.

Switch ports Fa0/1 to Fa0/23 go into VLAN 100 which could be your main LAN.

Anyway, so far I think the cabling is correct. Thus, what exactly is the problen?

jasonobrown · ‎07-17-2011

The configs were still in the equipment from before my brain injury. I couldn't do that again now if I had to, at least not yet. The problem that I'm having is that I can't get from the router to the modem. You stated that the only interface used on the router is fa0/1 which goes to switchport 48. What about the Content-Engine1/0? Does that interface not need a physical connection? Also, what type of cable should I be using to go from switchport 47 to my satelite modem? I figure it probably has to be either a T1 crossover or regular crossover cable, but I don't know which one. Thank you very much for taking the time to help me with this. I really appreciate it.

jimmysands73_2 · ‎07-17-2011

Depending on the cable modem, you might he to restart it, the MAC learned I believe is the one of PC or Router at the end of the cable modem. But you probably already tried that...so can you post the status of the interfaces?

I believe the ContentEngine is belongs to something more complicated then your try to setup.

http://www.cisco.com/en/US/docs/routers/access/interfaces/nm/hardware/installation/guide/concache.html

jasonobrown · ‎08-20-2011

You are correct about the content engine. I'm just going to forget about it for now. However I'm still unsure of which cable to use to connect my hughesnet satelite modem to switchport 47. Also I no longer have a computer that I can use to console into the switch and router. Why won't it let me telnet in?

jasonobrown · ‎08-20-2011

I just solved the telnet problem, so don't worry about that one.

jimmysands73_2 · ‎08-20-2011

Rule of thumb is between two like devices (sw to sw, rtr to rtr) use a crossover cable, but most devices can autosense and link up....but if you want to be sure, use the right cable. I would think a sat modem and switch would use a straight through. And the beautiful part is that you only have two choices, so try one, if not link, try the other, if still no link, let us know.

Good luck

jasonobrown · ‎08-20-2011

Yes you're right. The straight through works, but I still can't access the internet. Based on the configs that I posted above I think that my modem configuration needs to change or I will have to change something in the router or switch to adapt to this modem. It's a Hughesnet Satelite modem and I can't figure out how to make any changes to the configuration.

The Satelite Configs are:

Port 1 Addressing

LAN Port IPv4 Address: 192.168.0.1

LAN Port IPv4 Subnet Mask: 255.255.255.0

Addressing

Address Translation Within Local Domain: 72.168.139.107

jasonobrown · ‎08-20-2011

I was wrong about solving my telnet problem. I'm able to telnet into the switch from ip 172.16.0.1, but I'm unable to telnet into the router from any ip. I also tried to telnet into the router from the switch, but that doesn't work either.

jimmysands73_2 · ‎08-21-2011

Can you connect your PC directly to your satelite system, reboot your gear (least with Cox cable when Mac address changes your have to power down the cable modem for 20 seconds), then see if you can connect? This will atleast verify the functionality of the system...if this works, then we can start looking at the configs.

jasonobrown · ‎08-21-2011

It definitely works. I'm using it for my internet connection right now. I'm using a linksys router. I need to switch over to the cisco router and switch. I inserted a picture of a screen shot from the router I'm using now that shows the data it's pulling from the modem. If you still need me to plug the pc directly into the modem let me know and I will. Also I posted the same question on another forum with most of the same info, just re-organized it a little better. The link is

https://supportforums.cisco.com/message/3424851#3424851

posted