Default gateway / Primary Nameserver

[joseph wholey]

Is it likely that the default gateway is the same ip as the primary nameserver. Are they one in the same?

[Steven E. Protter · Accepted solution]

Shalom,

Yes, in many home environments the Internet router performs both functions.

It is less common but possible in large environments. There is nothing inherently wrong with this setup other than having a single point of failure.

SEP

[rick jones]

Not in the "enterprise" (in my experience) - default gateways and DNS servers are often separate systems - the former being dedicated routers and the latter being servers.

[joseph wholey]

So based on what your saying, nameserver and DNS are one in the same. I guess I need a little clarity on gateway, nameserver and DNS server.

[rick jones]

Default gateway - aka default router - the "next hop" destination to which your system will send IP datagrams when the destination is not in the same local IP subnet and there are no other explicit routes configured for that destination.

DNS Server/primary nameserver (and you should configure at least two DNS servers in resolv.conf...) are the systems to which your system will send DNS queries to do things like mapp a human friendly hostname to an IP address, or find the hostname for an IP address etc. (there are other sorts of queries such as finding the system to which mail should be sent for a given domain)

[kcpant]

Hi Joseph,

To add to the above, most large enterprise have two DNS servers for secuirty reasons in different DMZ: one for external (Internet) , one for internal network.External DNS servers handles queries from outside world for DNS name resolution of it's own domain, and internal DNS server works to resolve name requests made by it's internal hosts.

[Alexander Chuzhoy]

Enterpises prefer to have router(s) (usually brand names like HP or Cisco) acting as default gateway. Best environment includes more than 1 router for fault tolerance, thus if one fails-the users won't feel it.

DNS servers are installed on apropriate OS (UNIX/LINUX/Windows Server), per choice. Again having more than 1 is very recommended for fault tolerance.

However if we're talking about small setup and money is something you take into consideration- you can have both running on the same PC.

[timmy2006]

Deployment may differ depending on IT requests:
1. One ip all services -> routed in kind of DMZ.
2. One ip -> some services are on the same ip.
some - not.
3. Small one - all services on one ip (physical machine)
4. Routing performed by special device (router etc)
5. etc etc etc

I dont understand the question!

nslookup
> server YOUR_SERVER ip
> yahoo.com

route add default YOUR_SERVER

traceroute SOME_HOST_in_outer_nets.
or telnet yahoo.com 80