Linux - NetworkingThis forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.
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System:
RedHat 8.0 (fully updated from RHN)
Default install of DHCP
Network Details:
I have four different centers located in four different cities. Each center is connected via a Frame network (Hub and spoke).
Scenario:
I would like to create two RedHat DHCP servers in two of the four centers. One being a redundant/load sharing DHCP server. Each center has two separate subnets that need to be service via DHCP. (The two DHCP servers would have to service all four centers)
Question:
Is it possible to setup two RedHat DHCP servers to satisfy the above scenario? If so can someone post an example dhcp.conf file and any advice on how I would go about setting up this scenario. If not does anyone have a idea on an alternate solution that would be cost effective.
I haven't attempted a project this large with DHCP servers so any advice would be greatly appreciated.
Can you pass DHCP requests through a router? I though at I read at one time that router will not pass DHCP requests. Also whay not setup one location as the root domain and that other three as subnets. then have a DHCP, DNS server in each network. So it looks like this
That way if you lose the link to one network you don't lose two. Since you are using Linux there is no extra cost other than time and the cost of the servers.
Routers don't pass dhcp requests through by default. Keeps broadcast traffic down. I did think about that route, but I've also come across the dhcrelay agent. Any thoughts on that?
To be honest this is a little out of my league, but I would make each net self relient. Where I work we have 5 production locations and numerous reatil locations. I know for sure that each of the production locations has it's own DNS, DCHP and WINS servers. We experience link problems about two to three times a year. If we where to have the setup that you described, we would be down for those times. We do have a dial-up connection for a backup, but a 33.6- 56k connection is strained with the MRP system, let alone if it was passing DHCP, DNS and other requests (Our MRP uses a telnet connection to connect to the HP-UX server, so the traffic is light. But it gets really slow when it has 10 or so users running on the dialup connection).
I should have added one important detail to the scenario. I do however agree to your statement. The only reason I'm thinking of just two DHCP servers is the fact that we are running hub and spoke Frame connections now, but in the next month or two we will be converting to a IP meshed frame.
I've thought about putting DNS-DHCP servers in each location, but am reluctant to put any unnecessary servers at our remote locations. This is mainly due to the centralization of our support staff.
What is a "hub and spoke" and a "meshed" frame? We have a frame at work that connects us to the main site. It has a Cisco 1700 (use to be a 2500) router that sets between us and the frame.
As of the servers at remote locations. I am confident that you will have a fraction of the trouble that would have with a Windows server or workstation. We have a Win NT and 2000 server at work. Both need to be rebooted at least every other week. We also have an exchange server at our main site that is a ^%#&*.
If you have a Linux server (or UNIX) setup right, it should stay up for months or even years. I have one at home that had been up for 43 days. I had to reboot it becasue I screwed it up. I did one for a produce company that has been running for at least 8 months. They have yet to call me, so I take it that it has been up and running without a hitch.
I have no idea if you can setup a DCHP relay on a Linux box. I know you can on a Windows server. But I have little faith in Winodws reliability.
I am also interested in using a Linux box that is set up as a router to relay DHCP. I have a centralized Linux DHCP server in a public school network that I want to subnet. To date I haven't had any success in relaying BOOTP or DHCP between subnets. I'm using Slackware 8.1, could use 9.0. I need to subnet the school to gain greater control over student access to certain resources.
A hub and spoke network is where all of your "sites" are connected to a central location.
A meshed network is where all of your "sites" have direct connections to each other. The cost is a little higher, but all the redundancy your need is in a meshed network.
I found this link about a dhcp relay package for Linux, http://packages.debian.org/experimen...cp-relay.html.
There are also Mandrake PRM's that I found in a google search. So it seems that it is a pretty easy setup.
>Routers don't pass dhcp requests through by default. Keeps >broadcast traffic down. I did think about that route, but I've also >come across the dhcrelay agent. Any thoughts on that?
Any router may work as dhcprelay and what the problem ?
"meshed network" mean "one interface - many subnetworks" ?
Some example
host MACHINE_828 {
hardware ethernet 00:60:08:0B:83:0B;
fixed-address 172.20.18.17;
}
shared-network "Build_42-2" {
subnet 172.20.19.0 netmask 255.255.255.0 {
option broadcast-address 172.20.19.255;
option routers 172.20.19.1;
range 172.20.19.250 172.20.19.254;
}
subnet 172.20.18.0 netmask 255.255.255.0 {
option broadcast-address 172.20.18.255;
option routers 172.20.18.1;
range 172.20.18.250 172.20.18.254;
}
}
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