Fully qualified domain name

hassantalal785

Well i have read about FQDN in a couple of books and websites but i am still un able to understand that what is its advantage ? Secondly is domain-name command in Cisco IOS related to it as well ?Kindly explain in simple terms .

JeanM

hassantalal785 wrote: »

Well i have read about FQDN in a couple of books and websites but i am still un able to understand that what is its advantage ? Secondly is domain-name command in Cisco IOS related to it as well ?Kindly explain in simple terms .

Are you asking what FQDN is and when it's used? In the lab environment you won't have an FQDN unless you have your own active directory/dns. In the live environment FQDN is something like host.domain.com or router01.domain.com or switch01.domain.com...


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EV42TMAN

You'll run into FQDM stuff with Microsoft. and JeanM is right. When you set up Active Directory you create a domain. for this post i'll use mycompanyrocks.local then every object in active directory FQDM is Server01.mycompanyrocks.local, jsmith.mycompanyrocks.local etc.

networker050184

Don't worry about MS or AD, its just a complete DNS name. So for instance you want to be able to telnet to your router by its name rather than IP you need an entry in DNS to reach the device. The fully qualified domain name would be router.mycompany.com.

The domain name in the router configuration is what the device will use to complete names that are not fully qualified. For example you want to telnet to router 'r2' from your router. You can either do a telnet to r2.mycompany.com or you can add the domain name mycompany.com to your router and be able to telnet directly to r2 and the router will automaticly use the mycompany.com domain.

hassantalal785

networker050184 wrote: »

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The domain name in the router configuration is what the device will use to complete names that are not fully qualified. For example you want to telnet to router 'r2' from your router. You can either do a telnet to r2.mycompany.com or you can add the domain name mycompany.com to your router and be able to telnet directly to r2 and the router will automaticly use the mycompany.com domain.

This means that using FQDN enables me to telnet or access my other router (or a PC) by just writing its domain name instead of IP and FQDN would resolve the domain name for me which i have configured in the router ?

networker050184

FQDN = Fully Qualified Domain Name

You don't configure this on the router, you configure this on your DNS server to map the IP of your router to the name. You can then use the FQDN to reach the device.

A bit of light reading on DNS will probably clear this up for you easier than trying to look at it from a strictly Cisco point of view.

JeanM

networker050184 wrote: »

FQDN = Fully Qualified Domain Name

You don't configure this on the router, you configure this on your DNS server to map the IP of your router to the name. You can then use the FQDN to reach the device.

A bit of light reading on DNS will probably clear this up for you easier than trying to look at it from a strictly Cisco point of view.

What they said.

Think of DNS as a database, IP addresses vs. Human Friendly names...... FQDN has nothing to do with Cisco only.