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I think I understand dhcp and leasing and everything but I wanted some clarification on configuring it. Here is an example dhcpd.conf file I found w/ some questions in red... ...
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  1. #1
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    Can someone explain dhcpd.conf or point me to a good website?


    I think I understand dhcp and leasing and everything but I wanted some clarification on configuring it. Here is an example dhcpd.conf file I found w/ some questions in red...

    Code:
    # dhcpd.conf
    #
    # Sample configuration file for ISC dhcpd
    #
    
    # option definitions common to all supported networks...
    option domain-name "example.org";
    
    option domain-name-servers ns1.example.org, ns2.example.org;
    default-lease-time 600;
    max-lease-time 7200;
    
    option subnet-mask 255.255.255.0;
    
    allow booting;
    allow bootp;
    
    
    Not sure what this does. Can someone explain? 
    
    
    subnet 10.0.0.0 netmask 255.255.255.0 {
    option subnet-mask 255.255.255.0;
    option broadcast-address 10.0.0.255;
    
    
    default-lease-time 6000;
    max-lease-time 6000;
    
    
    Are hosts the clients that try to connect to the server? So in this case, ibmx3655 has a mac address of 00:14:5E:5A:31:57, and if it tries to connect to the server, it will obtain a static IP of 10.0.0.200? And you can basically put any settings in here that will apply to only this host when it connects?
    
    
    # this is the section for the x86
    host ibmx3655  {     
    hardware ethernet 00:14:5E:5A:31:57;
    fixed-address 10.0.0.200;
    option dhcp-parameter-request-list 1,6,15,60,43; 
    option subnet-mask 255.255.255.0;
    option domain-name-servers 10.0.0.20;
    option domain-name "site";
    option vendor-class-identifier "PXEClient";
      vendor-option-space PXE;
        option PXE.discovery-control 7;
        option PXE.boot-server 15 1 10.0.0.20;
        option PXE.boot-menu 15  15 "Tpm for OSd 7.1";
        option PXE.menu-prompt 0 "Tpm for Osd";
    }
    
    # this is the section for the x86
    host x41  { 
    hardware ethernet 00:0a:e4:2f:66:38;
    fixed-address 10.0.0.201;
    option subnet-mask 255.255.255.0;
    option domain-name-servers 10.0.0.20;
    option domain-name "site";
      option vendor-class-identifier "PXEClient";
      vendor-option-space PXE;
        option PXE.discovery-control 7;
        option PXE.boot-server 15 1 10.0.0.20;
        option PXE.boot-menu 15  15 "Tpm for OSd 7.1";
        option PXE.menu-prompt 0 "Tpm for Osd";
    }

  2. #2
    Administrator jayd512's Avatar
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    Quote Originally Posted by etranman1 View Post
    Not sure what this does. Can someone explain?


    subnet 10.0.0.0 netmask 255.255.255.0 {
    option subnet-mask 255.255.255.0;
    option broadcast-address 10.0.0.255;
    The subnet is used to divide a large network into smaller networks. This is useful for several reasons, all of which would depend heavily on specific needs and resources. But a quick example...

    You have 512 computers connected to a server. You can split that into 2 smaller subnetworks of 256, and then split one of those again to make 2 more subnets of 128... now you have 3 subnets (256 computers, 128 and 128 ). You can scale down all the way to 2 computers on a subnet.
    These could be assigned to various groups in a corporation, such as accounting or production machines.
    A layout like that can simplify the deployment of new software, or troubleshooting network connectivity.

    The netmask (subnet mask) can help determine how many computers is on said subnetwork.

    The broadcast address is a logical address where all computers that are connected can receive datagrams that are sent across the network.
    Jay

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  3. #3
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    that makes sense...Where do the numbers come from/mean? 10.0.0.0, 255.255.255.0, etc.

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  5. #4
    Administrator jayd512's Avatar
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    This wikipedia page should help with that a little better than I can...
    But the short answer is that your IPv4 address an 8-bit binary number.
    Jay

    New users, read this first.
    New Member FAQ
    Registered Linux User #463940
    I do not respond to private messages asking for Linux help. Please keep it on the public boards.

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