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My current setup is:

Cable modem dishes out 13 static IP's (/28), a GB switch is plugged into the cable modem, and has access to those 13 static IP's, I have about 6 "servers" in use right now.

The cable modem is also a firewall, DHCP server, and 3 port 10/100 switch. I am using it as a firewall, but not currently as a DHCP server.

I have plugged into the cable modem, two network cables, one which goes to the WAN port of a Linksys Dual Band Wireless 10/100/1000 router/switch. Into the linksys are a few workstations, a few printers, and some laptops connecting to wifi. I set the Linksys to use take static IP, and enabled DHCP for the workstations, printers, etc in The network for the Linksys is mostly self contained, backups go to a SAN, on that network, it all happens through that switch, over GB. But I also get internet access from it as well via the cable modem using one static IP.

This all works, however, I can not "see" the static IP machines when I am on the Linksys. I can get to them via ssh and other protocols, and if I want to from "outside", I open holes, like 80, 25, 587, 143, 22, etc.

The second wire, from the cable modem/fireall/switch just uplinks to the managed GB switch.

What are the pros and cons of this? I do not like giving up the static IP to the Linksys. I basically have a mixed network of public servers, and internal workstations. I want the public servers on public IP's because I do not want to mess with port forwarding and mappings.

Is it correct also, that if someone breaches the Linksys wifi, they still would have a hard time getting to the static IP range, just by nature of the network topology?

Today, just for a test, I toggled on the DHCP in the firewall/cable modem at range, the Linksys is n the range. At that point, all the static IP machines still had in and out access, but Linksys was unreachable.

The cable modem only has 10/100 ports, so I will not plug anything but the network drop into it, which is 50Mb/10Mb. Which makes me think this could be less than ideal, as transfers from the workstation network to the server network will be bottlenecked at 100Mb when I have 1000Mb available. I may not need to solve that, if isolation is better though. I do not move a lot of data, if any, from Linsys network to server network, so for it to pretend to be remote is ok.

Should I approach this any different?

I could enable DHCP on the cable modem/firewall, it should still send out the statics to the GB switch, but will also be a DHCP in range? I can then plug the Linksys into the GB switch, which is now picking up statics and the ranges, tell the Linksys to use or so.

Now, do I disable DHCP on the Linksys, and the cable modem/firewall will pass through the statics and ranges as well? Or, could I open a second DHCP pool on the Linksys? I guess doing so gives me network isolation again, but it is just the reverse of what I have now. But I get out of the bottleneck, not that the Linksys could ever really touch real GB speeds anyway, but the managed switch certainly can.

This is all because 13 statics are not that many. Right now, 6 "servers", the Linksys, a managed switch, a few SSL certs, and I am running out. I do not want to waste a static IP on the managed GB switch, or the Linksys, unless it provides me some type of benefit.

Final question, under my current setup, if I am on a workstation, sitting at, the Linksys, with GB, and I send a file over ssh to the static IP machine, is that literally leaving the internet, and coming back in, or does it stay local? To me it seems like:

Workstation ( -> Linksys DHCP -> Linksys Static IP -> Cable Modem -> Server ( and it hits the 10/100 ports on the cable modem, slowing me down.  But does it round trip the network, leave and come back in, limiting me to the 50/10 internet speeds?

*These are all made up numbers, I do not use default router IP's as I will one day add a VPN, and do not want collisions.

I need some recommendations, do I want one big network, or two isolated ones. Printers these days need an IP, everything does, I can not get autoconf/bonjour to be reliable on most printers. but I am also not sure I want the "server" side of my operation to be polluted by the workstation side of my operation.

Unless there is some magic subetting I have not learned yet, here is what I am thinking:

Cable modem 10/100, has 13 static IP, publicly accessible ->
Enable DHCP on the cable modem ->
Cable modem plugs into managed switch ->
Managed switch gets ssh, telnet, https admin management address ->
Managed switch sends static IP's to to servers ->
Plug Linksys into managed switch, giving it static internally in Linksys admin ->
Linksys gets assigned 10.1.10.x as its DHCP sending range ->
Local printers, workstations, iPhones etc, connect to this ->
( Do I enable DHCP or disable it on the Linksys, just define a non over lapping range, or create an entirely new DHCP at, I think I am back isolated again with that method too? )

Thank you for any suggestions. This is the first time I have had to deal with less than a /24, and most are larger than that, but it is just a drop to a cabinet. Otherwise, it's a router, a few repeaters, and soho stuff that is simple, with one IP. I know a few may suggest going all DHCP on the servers, and I may one day, just not now, there has been too much moving of gear for me to be interested in that, and I would want something in the Catalyst series to deal with that.

share|improve this question

closed as not a real question by Breakthrough, studiohack Feb 23 '11 at 20:55

It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center.If this question can be reworded to fit the rules in the help center, please edit the question.

Why don't you put your question in the subject line? – cmcginty Apr 15 '10 at 20:28
I thought my subject summed it enough that someone reading it would know if they had the experience to help. Why is everyone so worried about form? Ask a question, hope to get an answer. I try to answer questions, usually I am beaten by someone else faster. I didn't put in Sub: HELP!; if you want to suggest I made a mistake, please suggest a solution. Not all of us spend hours a day here, and know the nuance of making a perfect post. I will certainly resist posting questions now, as I sit for 5 minutes wondering what the acceptable subject is. I read the FAQ b4, nothing about subjects. – user17245 Apr 16 '10 at 2:50
How about this for a Subject Header "Huge Network Need Help to Configure"... this question for me is almost beyond the scope of this board I gave up reading 1/3 the way; you might just be better off hirring a local IT Tech who is familiar with business network infastructure! - Hope that helps! – Iceking007 Feb 18 '11 at 14:42
"Why is everyone so worried about form?" Without form, this community would fall apart. Your "question" is poorly worded, and contains far too much writing and off-tangents. Change the title to a legitimate question, and remove the excessive writing from the body. Normally I would do this for you, but you seem more then capable of doing it yourself, and I'd much rather flag this question if you don't. If you don't want to get any answers, then don't follow my suggestions. And remember - this is a Q&A website, not a forum. Factual information belongs here, opinions belong on forums. – Breakthrough Feb 22 '11 at 17:53

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