dhcp 2

[mikemes]

how do you setup dhcp on a cisco 3600 or 2600 series router using 12.0

 

[JasonC]

How do you want to set it up?&nbsp;&nbsp;Are you looking to forward address's from a specified DHCP server to another network or are you looking to actually configure a DHCP Server?<br><br>JasonC

 

[Guest_imported]

Hope you dont mind me helping you clarify the question, Jason.<br><br>What we need to know is, Are you looking to get the DHCP<br>broadcasts forwarded from one segment (network) to another,<br>so they can reach a DHCP server (hopefully this is it) 'OR'<br>are you saying you want the router to be a DHCP server<br>itself?<br><br>Trying to make the router a DHCP server would be a almost<br>strange thing to do, when you have alternatives like running<br>it on a server platform like NetWare, NT4 server, or Linux.<br><br>Remember, anyones router performs best when it only has to<br>do one thing, route.<br><br>Leroy&nbsp;&nbsp;MCNE, MCSE, CCNA, CCDA

 

[miker]

Running DHCP on a router a strange thing to do?&nbsp;&nbsp;&nbsp;I'm curious as to why you say this?&nbsp;&nbsp;I don't want to start an argument, but I'm interested in your point of view and why you feel this way.&nbsp;&nbsp;So please don't take this the wrong way as I'd prefer a debate over this instead of a flame ware.<br><br>I have DHCP running on two seperate routers and am in the process of setting it up on another.&nbsp;&nbsp;&nbsp;In my network it works great.&nbsp;&nbsp;&nbsp;To me, this elminates one more thing in the network that could go wrong.&nbsp;&nbsp;It makes perfect sense to me to run this on the router, as it helps reduce costs.&nbsp;&nbsp;You don't need to purchase a seperate server, actually two if you want redundancy.&nbsp;&nbsp;You don't need to purchase additional software, unless you are using Linux or FreeBSD (personal favorite) and have good reliable open-source DHCP server software.&nbsp;&nbsp;You also don't need to purchase some type of tape backup and tapes to backup those servers.&nbsp;&nbsp;&nbsp;Since I already back up my router configs - doesn't everyone? - I know I've always got a backup.&nbsp;&nbsp;Yes, what you say is correct, a router will work best if it does only one thing, but in todays IT world, that's kind of unrealistic.&nbsp;&nbsp;Otherwise, cisco's IOS would not be so feature packed.&nbsp;&nbsp;&nbsp;If you're router is doing a dozen other CPU intensive tasks, I would advise not to put DHCP on it, but otherwise, use it.&nbsp;&nbsp;&nbsp;If you're using IPSec or some other tasks that are eating your CPU's utilization, then DHCP on the router isn't the way to go.&nbsp;&nbsp;But if you're router is sitting at 5% utilization, do it.&nbsp;&nbsp;&nbsp;You paid a good deal of money for that cisco router, put it to work for you!&nbsp;&nbsp;So I don't feel it is a strange thing to do.&nbsp;&nbsp;&nbsp;If you're router is already working pretty hard and taking on a good size load, don't burden it down further with DHCP, but instead, use a server platform for DHCP.&nbsp;&nbsp;But, if your router isn't doing a whole lot and it's utilization is very low, put DHCP on it, it's easy to configure and maintain.&nbsp;&nbsp;&nbsp;All this though is dependent upon what model router you have and what other functions it is currently doing.

 

[miker]

ip dhcp database <A HREF="ftp://usernameassword@10.10.10.10/router-dhcp" TARGET="_new">ftp://usernameassword@10.10.10.10/router-dhcp</A><br>ip dhcp excluded-address 172.20.0.0 172.20.9.255<br>ip dhcp ping packets 1<br>!<br>ip dhcp pool FOO<br>&nbsp;&nbsp;&nbsp;network 172.20.0.0 255.255.0.0<br>&nbsp;&nbsp;&nbsp;domain-name organization.com<br>&nbsp;&nbsp;&nbsp;default-router 172.20.0.1 <br>&nbsp;&nbsp;&nbsp;dns-server 172.20.0.2 172.20.0.3<br>&nbsp;&nbsp;&nbsp;lease 0 4<br><br>The ip dhcp database is optional, it's only if you want to keep some sort of database of the MAC addresses and what IP address they were assigned.&nbsp;&nbsp;The excluded-address keeps those addresses from being assigned to anyone.&nbsp;&nbsp;&nbsp;You can use those on your network for servers or any workstation that requires a static address.&nbsp;&nbsp;All you do is create a DHCP pool and name it, in the above example, it's named FOO.&nbsp;&nbsp;&nbsp;You specifiy the network you want to be used, again, this one is using the 172.20.0.0 class B segment.&nbsp;&nbsp;Remember though that only addresses starting with 172.20.10.0 - 172.255.255.254 will be handed out since we've excluded 172.20.0.0 - 172.20.9.255.&nbsp;&nbsp;You'll need to specify the domain-name your organization uses also.&nbsp;&nbsp;You setup what the default gateway for those machines will be, in this case, 172.20.0.1 and what DNS server they will use.&nbsp;&nbsp;In my example, I have two listed, a primary 172.20.0.2 and a secondary 172.20.0.3.&nbsp;&nbsp;Since these addresses are excluded from the DHCP pool, I can assign them to servers, the routers ethernet interface or any device that needs a static IP address.&nbsp;&nbsp;&nbsp;The lease on any IP address pulled from this pool will last only 4 hours.&nbsp;&nbsp;It's specified in days and hours.&nbsp;&nbsp;You can have the lease expire in 7 days&nbsp;&nbsp;and 12 hours if you wanted, though that's not advised, by using &quot;lease 7 12&quot;.<br><br>This is a basic configuration and more than enough to actually get it up and running on your router.&nbsp;&nbsp;If your organization uses WINS along with, or instead of DNS, that can be accomplished using &quot;netbios-name-server 172.20.0.2&quot;.&nbsp;&nbsp;&nbsp;There are other options that be set to tailor this to your organizations needs.&nbsp;&nbsp;Create a basic pool and then play around with it.<br><br>Hope this helps.

 

[JasonC]

And in case you wanted to forward the IP address's to another network segment config the router with a helper address.<br><br>interface Ethernet0<br>&nbsp;ip address 10.x.x.x 255.0.0.0<br>&nbsp;ip helper-address 10.x.x.x<br>&nbsp;bandwidth 10000<br>&nbsp;ipx network xxxx<br>&nbsp;no ipx route-cache<br>&nbsp;priority-group 1<br><br>You can configure this by doing the following:<br>conf t<br>int e0<br>ip helper-address x.x.x.x<br>CTRL Z<br>and copy run start<br><br>your all set if you already have a DHCP server<br><br>JasonC<br> <p> <br><a href=mailto:jcusick@visto.com>jcusick@visto.com</a><br><a href= > </a><br>

 

[COPA]

I don't know if any of the guys who discussed this are still using the Forum but I have a question.

Is the domain-name config statement relevant to NT or just when configuring for Website Access ???

Excuse me for dragging up an old thread but I've been using this config as a template to follow since April and am just about to put it into live operation. The Config I've got works without it in testing , but should I have it in there for some (not obvious) reason ???? Paul C.
s-)

 

[wybnormal]

either the domain-name just adds the someone.com qualifier to any name that did not have the fully qualified domain name to start with.

Here is a clip from Cisco's docs about it:

http://www.cisco.com/univercd/cc/td/doc/product/software/ssr83/tsc_r/54008.htm#xtocid1120740

::Snip::
The global configuration command ip domain-name defines a default domain name the terminal server uses to complete unqualified host names (names without a dotted domain name appended to them). The syntax of this command follows:

ip domain-name name
no ip domain-name
The argument name is the domain name; do not include the initial period that separates an unqualified name from the domain name.

The no ip domain-name command disables use of the Domain Name System.

Example:
This command

!
ip domain-name cisco.com
!

defines cisco.com to be used as the default name. Any IP host name that does not contain a domain name, that is, any name without a dot (.), will have the dot and cisco.com appended to it before being added to the domain name system.

By default, IP Domain Name System-based host-name-to-address translation is enabled. To enable or disable this feature, use the ip domain-lookup global configuration command as follows:

ip domain-lookup
no ip domain-lookup
The no variation of the command disables the feature; the ip domain-lookup command restores the default.

:::snip::::

Mike S