Configuration and management of Linux-dns server (top)

Configuration and management of DNS servers

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The first thing to know is the following files related to domain name resolution
/etc/hosts-Early (DNS) method for resolving host names, typically consists of three fields: IP, host full domain name, alias
/etc/resolv.conf--Specifies the parameters of the DNS server used in the DNS client.
/etc/nsswitch--This file is used to define the search order of the network database, such as: host name, user password, network protocol and other network parameters.
/ETC/HOST.CONF-parser configuration file that specifies how the library is parsed. There is usually a command that specifies the order of queries for the host.
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Types of DNS servers

1. Primary Domain name server (master server)
The primary domain name server is the source of all information in a particular domain, and it loads the domain information from the local disk file created by the administrator. Configuring the primary Domain name server requires a complete set of
Configuration file, which includes the master configuration file, the zone file for the forward domain, the zone file for the reverse domain, the cache file, and the local host reverse parsing file.
Note: There can be only one primary name server in a domain, but sometimes in order to decompose the domain name resolution task, you can create one or more secondary name servers.
2. Secondary domain name server (slave server)
is a backup of the primary domain work, also known as backup domain name server, with the majority of the main server functions, for the secondary name server only need to configure the Master profile, cache
Files and local anti-parsing files without the need to configure zone files, because zone files can be transferred from the primary domain name server and stored on the local hard disk of the secondary domain name server.
3. cache domain Name server (caching only server)
The cache name server records each query result from the remote server to the domain name server and then saves it in the cache for future queries of the same information. Because the cache
The server itself does not manage any domains, so you only need to cache the files when you configure the cache server.
4. Forwarding server (forwarder server)
The forwarding server can send DNS requests that will be resolved to servers outside the network, which can keep other servers on the LAN hidden from the Internet.

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Bind installation and start-up

Bind is a Linux-implemented DNS server package, and almost all Linux distributions contain bind.
I. Installation of BIND
There are two ways to install bind under Linux: One is to select the DNS software during the system installation phase, and the other is to install the bind package separately after the system is installed.
You can use the following command to query whether DNS is installed: #rpm-qa |grep bind
If the system does not have bind installed, you can install bind as follows:
① first mount the installation disk
#mount/dev/cdrom
#cd/media/cdrom/centos/rpms (This is the CentOS4 package directory)
#cd/mnt/cdrom/redhat/rpms (This is the REDHAT9 package directory)
Find the following RPM package from the first disk:
caching-nameserver-7.3-3.noarch.rpm
Find the following RPM packages from the second diskette and fourth discs:
bind-libs-9.2.4-2.i386.rpm
bind-utils-9.2.4-2.i386.rpm
bind-9.2.4-2.i386.rpm
bind-chroot-9.2.4-2.i386.rpm
bind-devel-9.2.4-2.i386.rpm
(whichever is the actual version number, of course)
② Copy the above package to a directory on the system (such as/root) and install it to the system using the following command:
#rpm-IVH bind*.rpm
#rpm caching-server*.rpm
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DNS Start-up

1. Implementation in graphical mode: "Application"-"System Settings"-"Server Settings"-"services"
Select the named option in the Service Configuration window to perform startup, shutdown, restart, and so on for the named service.
2. Implement at the command line:
① using command #/etc/rc./init.d/named {start|stop|restart|status}
② can also use the command #service named {start|stop|restart|status}
(In fact, the internal implementation mechanism of the service script is to invoke the corresponding script in the/ETC/RC.D/INIT.D directory, so these two commands are actually the same)
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configuration files for DNS servers

Configuration and management of Linux-dns server (top)