Visit Jeremy's Blog.
Go Back > Forums > Linux Forums > Linux - Networking
User Name
Linux - Networking This forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.


  Search this Thread
Old 09-30-2005, 04:35 PM   #1
LQ Newbie
Registered: Jul 2005
Distribution: RedHat Enterprise ES
Posts: 6

Rep: Reputation: 0
help with dhcpd.config file to assign address's to clients on another subnet

Am having problems with my dhcpd.conf file assigning address on another subnet on the same network. The one that I have all of my server's and networking gear is on a wtih an netmask of I would like to assign all of the client computers a subnet with a netmask of I have both subnet's declared in the file and the ranges I want to assign ( dhcpd will start but will not assign the correct address. Maybe I should use a shared network declaration or group declaration. Not sure which. Running on RedHat Linux 3.x Enterprise. Thanks for any input.
Old 09-30-2005, 05:09 PM   #2
Alien Bob
Slackware Contributor
Registered: Sep 2005
Location: Eindhoven, The Netherlands
Distribution: Slackware
Posts: 8,559

Rep: Reputation: 8106Reputation: 8106Reputation: 8106Reputation: 8106Reputation: 8106Reputation: 8106Reputation: 8106Reputation: 8106Reputation: 8106Reputation: 8106Reputation: 8106
You know that on the router between those subnets, you have to run a dhcprelay? Because otherwise the dhcp client requests will never reach the dhcp server.

If this is not the cause of the problem, then you might want to post your dhcpd.conf file. You don't want a shared-network declaration, since that does not apply to your network topology, and a group declaration would make little sense (but maybe your dhcpd.conf file will show the sense of that).

Then again, I might interpret your question falsely, and you mean you have only one physical network segment, and want to use two separate IP subnets on it? In which case you should use a shared-network declaration.

Old 10-03-2005, 09:42 AM   #3
LQ Newbie
Registered: Jul 2005
Distribution: RedHat Enterprise ES
Posts: 6

Original Poster
Rep: Reputation: 0
This is for a WISP setup, I have two NIC's in my DHCP server. I am running a SonicWall firewall and want my clients on the DMZ side of the firewall (2nd subnet), and all of my networking/server's on the other (1st) subnet. The clients need to obtain authorization from a server on the other (1st) subnet, and yet have full internet access on the (2nd subnet) DMZ. (I have the LAN side running a content filter and IDS, and Managed A/V protection). The DMZ is wide open. From what you stated, I can see two fix's for this. 1. Assign 1 IP on the same subnet to eth0 and plug it into my DMZ Switch and use it to assign DHCP, and then build a route in RedHat to eth1, which is on the other subnet. Or, do some routing in the SonicWall appliance from the DMZ to the LAN. What do you think? Thanks so much for the reply. You have been a great help. I was able to get the DHCP working on my DMZ Switch with the current DHCP.confg. It did assign the correct IP's and subnet, DNS servers seems like all I need is to work on my routing. Any ideas would be great...and again thanks a million.


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
dhcpd subnet declaration problems in dhcpd.conf vcrispo Linux - Networking 6 07-15-2005 10:32 AM
Config DHCPD for non-direct connected subnet desmondwck Linux - Software 0 05-14-2004 09:36 AM
RH9 and DHCPD issues with some clients paradigm Linux - Networking 5 11-03-2003 03:08 AM
Serving DNS IP to Macintosh clients via DHCPD Darieus Linux - Networking 1 08-08-2003 10:06 AM
dhcpd / tftp Config help please BaerRS Linux - Networking 3 07-02-2003 11:36 PM > Forums > Linux Forums > Linux - Networking

All times are GMT -5. The time now is 12:35 AM.

Main Menu
Write for LQ is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration