Don't get into routing, they said.. It's rage-inducing, they said!

[Garacesh]

Well.. They were right..

Threw together a small subnet in CISCO Packet Tracer, working on building a small network, pretty much just for funs (and as a learning experience).

 

So, I've got a small network set up where the workstations can communicate with each other. Wonderful. Let's try and emulate an internet connection, shall we?

Big mistake.

 

Cut to a few days later and I regret everything - but I'm determined to figure out how it works.

I've tried way more things than I can list - or even remember.. Different IP's.. Static route settings, (blindly) attempting to use RIP - short of putting the 'ISP Router' on the same network.

 

Anybody mind taking a look at what I've got and pointing me in the right direction?

Edited October 11, 2012 by Garacesh

[SYNACK]

Hadn't seen this before, shall have to find a download for it and give it a go on a VM at some point, might refresh my memory a bit

[Garacesh]

Aha! I figured it outish...!

I needed to Bridge the routers.. Although I'm thinking putting a bridge in-between them is cheating.. Ought I to set something in the config?

Diving in at the deep end is often an odd experience when it comes to gaining new knowledge..

[Dos_Box]

Moving to Networks forum.

[SYNACK]

Aha! I figured it outish...!

I needed to Bridge the routers.. Although I'm thinking putting a bridge in-between them is cheating.. Ought I to set something in the config?

Diving in at the deep end is often an odd experience when it comes to gaining new knowledge..

 

If you can put up a screenshot of the topology we may be able to help easier, could just be that the routers are not MDX/MDIX enabled so need a crossover, a problem solved by the bridge.

[british_government]

just had a look at your original upload, for info, assuming the router is yours you wouldn't use RIP,

set a default route on your router for anything it doesnt know and just shove it out of your interface to the internet either with:

 

ip default-network 12.16.218.35

or

ip route 0.0.0.0 0.0.0.0 fastEthernet 0/1

 

EDIT: and just looked at your vlans, VLAN1 should always be management vlan, so really you should use another for all your machines, or possible a separate vlan for desktops, servers and wireless devices to isolate potential issues. I can put together an example if you want? Or I can butt out

Edited October 12, 2012 by british_government

[Garacesh]

I can put together an example if you want? Or I can butt out

Oh, don't consider yourself a burden. By all means, go for it.

Pretty much going-in-blind with this, learning as I go along and make (many.. many..) mistakes. Building a network isn't exactly in my job description as an apprentice, but it's something I'd like to learn regardless.

 

I wasn't aware VLAN1, by standards, was management vlan - but I know zilch about inter-vlan-routing, so I think I'll leave sorting that one out until I've got this 'internet connection' sorted.

 

If you can put up a screenshot of the topology we may be able to help easier, could just be that the routers are not MDX/MDIX enabled so need a crossover, a problem solved by the bridge.

Sure. See the uploaded pics. Granted, there's only 3 workstations on the map, but I've accounted for the port usage in the switches and ensured DHCP has a large enough pool (and then some, for future expansion).. Anything else y'might need, just go for it.

Also, I don't even know if I've done 'the internet' right.. So I might even have b0rk'd that up.

 

(Also, yes, it says Port 23: Modem instead of Router. My bad.)

Edited October 12, 2012 by Garacesh

[twin--turbo]

a bridge is a router.

[twin--turbo]

Wonderful. Let's try and emulate an internet connection, shall we

 

what do you exactly mean by this?

 

you have a switch connected to one side of the router for the internal network correct? and somethign on the outside being th internet?

 

and vlan1 can be used just fine.

 

to actualy connect the router to the internet your going to need to either have a public IP for each client PC or be running NAT.

 

Rob

[Garacesh]

Well - Like I said - Going in blind here, that's why I'm using Packet Tracer and not any of the spare switches we have lay around . The 'internet' cluster is basically just another network with an outward-facing router. Nowhere specific, it could be Google, Edugeek or Andromeda Research Corporation. Just another network that isn't part of mine. (Or at least, that's the plan!)

[british_government]

vlan demo.zip

 

See attached, I have just put that together quickly using a few different vlans. There are many benefites of a system like this, for example security as you can apply different access lists to different vlans for different permissions.

 

As a basic example only machines on the ADMIN vlan can telnet to the switch, in practise you would have this as ssl and probably only 1 or 2 machines, but the idea is the same.

 

What you could try is assigning an access list so wireless devices can only ping the server vlan, but no others?

 

And another note, the only downside to vlanning really is that inter-vlan traffic goes through your router rather than just the switch, as it is changing networks so must be routed. The router is running a simple rip setup.

[twin--turbo]

Have you got routing tables on the client devices that specify the router to use to find the other network?

 

Rob

[twin--turbo]

your diagram also shows a 12.11.x.x network connected to a 12.16.x.x does that fall in the same subnet?

 

Rob

[Garacesh]

[ATTACH]15570[/ATTACH]

 

See attached, I have just put that together quickly using a few different vlans. There are many benefites of a system like this, for example security as you can apply different access lists to different vlans for different permissions.

Can't. Incompatible. What version are you using?

 

Have you got routing tables on the client devices that specify the router to use to find the other network?

your diagram also shows a 12.11.x.x network connected to a 12.16.x.x does that fall in the same subnet?

No and no D:

I have default gateway set, but since nothing connects to the router without hitting a switch first, the switch sends the traffic forward. Plus, now with that bridge there (for now..) a client on the network can ping the router inside the cluster (seemingly) without a problem, so I wasn't sure if I needed a routing table..

The 12.11.x.x and 12.16.x.x aren't meant to be on the same network - they're just representing external IP addresses, 12.11 being someone else's network somewhere - anywhere - it doesn't really matter too much. It's really the only way I could think of representing an internet link.

[british_government]

Can't. Incompatible. What version are you using?

5.3.2, let me know if you cant get hold of it, I think I have a copy I can upload.

[Mehmet]

EDIT: and just looked at your vlans, VLAN1 should always be management vlan, so really you should use another for all your machines, or possible a separate vlan for desktops, servers and wireless devices to isolate potential issues. I can put together an example if you want? Or I can butt out

 

Why should VLAN 1 always be the management VLAN? I thought it was considered bad practice to have your management VLAN and your native VLAN on the same VLAN.

[british_government]

Why should VLAN 1 always be the management VLAN? I thought it was considered bad practice to have your management VLAN and your native VLAN on the same VLAN.

 

The default management VLAN is VLAN1, and what you are taught when you take CCNA. VLAN1 should never be assigned as access to any port, and actual end user devices should be on a different VLAN. In reality your management VLAN can be anything, the standard is VLAN1, but as long as it is configured correctly and no ports are on the VLAN it doesn't matter but why re-invent the wheel?

[Mehmet]

The default management VLAN is VLAN1, and what you are taught when you take CCNA. VLAN1 should never be assigned as access to any port, and actual end user devices should be on a different VLAN. In reality your management VLAN can be anything, the standard is VLAN1, but as long as it is configured correctly and no ports are on the VLAN it doesn't matter but why re-invent the wheel?

 

As long as you remember to remove ports from VLAN 1, or shut them down; which many people don't seem to do.

[british_government]

As long as you remember to remove ports from VLAN 1, or shut them down; which many people don't seem to do.

 

If you design for bad config you will get a bad config. When you setup your management VLAN and all your VLAN's you should make sure ports are disabled or on a correct VLAN. DHCP should not be running on that VLAN anyway so even if you leave a port open on your management VLAN and somebody connects they will get a 169 address and can do nothing without knowing details of your management scope.

[Garacesh]

Well, I decided to take a step-up from this and after about a week or so of spending lots of time researching, doing things wrong and asking questions, I'd managed to 'build' a network with 3 different VLAN's, 3 different subnets, and inter-VLAN routing.. And it worked

 

Now whenever I try to make changes, Packet Tracer crashes if I save them ;_; So I haven't got working an internet link, or VOIP, which were the next things I wanted to do. D'oh!

[Davit2005]

Sorry slightly off subject, where can I find a copy of Packet Tracer on Cisco's web site to download. Had a CCNA qualification a few years ago and had a copy of packet tracer somewhere .