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Hello all!

 

i have a client that has a Cisco 1803 serving as a bridge for two different subnets; the only problem is that both of the subnetworks are all gigabit and this router isn't :rofl: :rofl: :rofl:

 

so i want to know, for a reference for this client, a good replacement for this router; it must support gigabit connections.

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A Gigabit layer 3 switch. It will support your bridge. You could do a router/firewall solution like of pfsense, monowall, or smoothwall. That would also do what you want.

in this case it's just a bridge for the two subnetworks; that network is such a mess...

" as a bridge for two different subnets"

So your saying he is running 2 different address schemes over the same wire?

Why??

" network is such a mess..."

Well why don't you fix it, clearly if he is asking you for hardware suggestions you should be able to provide more ideas on clean up.

It is must better to fix any mis configurations in the network before just throwing hardware that can do what he is currently doing, if what he is doing is a cluster.. Bridging 2 different subnets together seems like a cluster to me - but also missing info, and possible miscommunication to what is actually going on.

But in general no I would not suggest you run 2 different address spaces over the same wire.

" as a bridge for two different subnets"

So your saying he is running 2 different address schemes over the same wire?

Why??

" network is such a mess..."

Well why don't you fix it, clearly if he is asking you for hardware suggestions you should be able to provide more ideas on clean up.

It is must better to fix any mis configurations in the network before just throwing hardware that can do what he is currently doing, if what he is doing is a cluster.. Bridging 2 different subnets together seems like a cluster to me - but also missing info, and possible miscommunication to what is actually going on.

But in general no I would not suggest you run 2 different address spaces over the same wire.

 

eheh kind of expecting to see your opinion here :)

 

about the subnets: it's two different companies linked together by this router, in which one of them needs to access the other one resources. And yes, i want to fix it completely but the client just needs this particular problem to be solved right now; if done correctly then the odds of fixing this whole mess are greatly increased (they have a lot of other problems, server wise as well).

Also my issue is... i don't know jack about Cisco routers :) and no one knows in both companies if that router belongs to them or if it even belongs to the ISPs (them have both). :/

If they are sharing resources - then they can not be on 2 different address schemes with a bridge.. It would have to be routing..

What are the addresses used, are we sure the cisco is just not acting like a switch? You state 1803, so that is

Cisco 1803 G.SHDSL Router

G.SHDSL 4 Wire Interface with ISDN S/T Backup Port

So to be honest, I have to assume the wired interfaces are just lan ports and its acting like nothing more than a switch for you lan side. If that is the case and you want gig.. Just get any gig switch, managed, unmanaged, whatever and disconnect your wireds to your cisco, connect them to the new switch.

And then connect a cable from the switch to your cisco that is your gateway.. There you go gig lan with 100mbit uplink to your gateway. Since I highly doubt your internet is over 100mbit.

Does that help? If you want can you post config of this cisco? Some details of your IP space on 2 different machines -- for example ipconfig /all from machine in each company.

Like I said earlier, get a layer 3 switch.  Here is how it would be configured.  Layer 3 is routing, so a layer 3 switch can route to different subnets.

 

Substitue the Business network subnets with your own, I just made up numbers so that you can easily see that they are completely different subnets residing on the same switch.  These subnets can route to each other because this is a layer 3 switch...layer 2 does not support this function.

 

 

post-118098-0-88619300-1383748698.jpg

^ that is all fine and good sc302, but to be honest with the complete lack of info here and the fact stated they are sharing info, etc. I have to think they are all on just 1 network and they could just buy any ole dumb switch to get to gig.

We really need more info to fully help.

For starters my requested ipconfig /all from the 2 companies machines would be of great help - and the configuration of this 1803 would be fantastic..

Can you shell to the router and do a show run and then post that?

he mentions 2 different subnets.  Could be different tennants of the same building all wired into the same closet, that is how I am seeing this.  They put in a router to be able to handle the routing tables between the two networks, a bit sloppy...even when that router was in its hay day a cheap layer 3 switch would have done exactly what they need.  This was sloppy from the start, put together with whatever they had laying around. 

I hear you that he mentions "subnet" and to me and you yes that should mean 2 different networks say 192.168.1.0/24 and 192.168.2.0/24 -- but then in the same sentence "bridge" is stated.. Which makes no sense.

 

So until see some actual details of what each client shows, or the config from the 1803 itself I have no idea what is actually going on.  The 1803 is a pretty simple device - not much more than a fancy soho router.. I am leaning towards they are on just 1 network with the 1803 ports being used as switchports.

 

Lets see what info we get back once he gets to the client location and can give us some actual details.

I hear you that he mentions "subnet" and to me and you yes that should mean 2 different networks say 192.168.1.0/24 and 192.168.2.0/24 -- but then in the same sentence "bridge" is stated.. Which makes no sense.

 

So until see some actual details of what each client shows, or the config from the 1803 itself I have no idea what is actually going on.  The 1803 is a pretty simple device - not much more than a fancy soho router.. I am leaning towards they are on just 1 network with the 1803 ports being used as switchports.

 

Lets see what info we get back once he gets to the client location and can give us some actual details.

 

well, not today unfortunately (office was closed). oh and i don't have access to the 1803, so no configuration dump (that's what i'm trying to figure out who's responsible for that router)....

Well if you don't have access the router, ipconfig /all from machines from each company should tell us if your different segments or just same one, etc.

 

You don't have access to the router why?  You don't know login, don't know the IP?  You should be able to console into it and get the config.  Did you try just default username and password?

because

 

Well if you don't have access the router, ipconfig /all from machines from each company should tell us if your different segments or just same one, etc.

 

You don't have access to the router why?  You don't know login, don't know the IP?  You should be able to console into it and get the config.  Did you try just default username and password?

 

don't know the login AND the IP to it. :) why? because i don't know (and i'm pretty sure no one does in this client :/) who's the owner of that router: the ISP's, the client...or else I'll just plugin a console cable and recover the router buy resenting the credentials, but i can't since i don't know who's the owner of that.

It isn't anything relating to cisco. It relates to everything network. A simple network tool to ping the network would suffice, you can easily narrow down the network. Generally routers will respond to ping on the inside network, computers will not if the firewall is enable....at least not by default. Even if the computers did respond it would be fairly easy to tell what is a computer and what isn't. There are plenty of mapping tools that will tell you what the device is that responds, that would take considerably longer.

It really is more troubleshooting and mapping a network out than cisco or any brand related thing. My laptop has a lot of goodies on it to do network inventory, scans, as well as other troubleshooting tools.

Wow, reading this and shaking my head, when I had my IT Business, first thing I did was take control of customers network appliances anything i couldn't get into was replaced by something I could.

Also I never went on forums asking for advice. a professional should know what his client needs or requires, if not get out of the biz.

 

and I'm nowhere near having the expertise of Budman, enjoy reading his answers to people's networking issues.

anyhow I shut my biz down because too much competition and I got a job offer that paid more than I was making in business.

"don't know the login AND the IP to it. :) why? because i don't know (and i'm pretty sure no one does in this client"

Um as sc302 was getting at - its quite easy to deduce this stuff.. for starters from any client that you can ipconfig from you can see what the gateway IP is, this is going to be the IP address you can access the cisco device at.

As to console into it - yeah this is again 101 networking stuff. How do you support clients and not know basic cisco stuff? Not talking how to enable bgp with access lists or anything.. just basic console in and show run.

Anyhoo -- just want to help, not here to judge your skill sets.. So if you can post what you can, say an ipconfig /all from clients in the 2 different networks we can start to get some data to work with.

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