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Gauvenator

Member

Registered: 2008-04-03

Posts: 172

how to find subnet and netmask?

Question in the title.  I need to know to setup my dhcpd server...

Last edited by Gauvenator (2008-05-24 19:44:03)

skymt

Member

Registered: 2006-11-27

Posts: 443

Re: how to find subnet and netmask?

The long answer involves a lot of math.

The short answer is to pick one of these two networks reserved for private use:

* Subnet: 192.168.0.0, netmask = 255.255.0.0, example IP: 192.168.1.42
* Subnet: 10.0.0.0, netmask = 255.0.0.0, example IP: 10.2.5.99

I use and recommend the second, simply because it's easier to type.

[Edit: fixed brain-fart. No offense taken, tomk!]

Last edited by skymt (2008-05-26 15:05:30)

Gauvenator

Member

Registered: 2008-04-03

Posts: 172

Re: how to find subnet and netmask?

The long answer involves a lot of math.

The short answer is to pick one of these two networks reserved for private use:

* Subnet: 192.168.0.0, netmask = 0.0.255.255, example IP: 192.168.1.42
* Subnet: 10.0.0.0, netmask = 0.255.255.255, example IP: 10.2.5.99

I use and recommend the second, simply because it's easier to type.

I tried the 2nd and I get this error when starting dhcpd:

/etc/dhcpd.conf line 3: subnet 10.0.0.0 netmask 0.255.255.255: bad subnet number/mask combination.
subnet 10.0.0.0 netmask 0.255.255.255 
                                  ^
Configuration file errors encountered -- exiting

Sure you didn't mean 255.255.255.0?

Last edited by Gauvenator (2008-05-24 20:36:01)

tomk

Forum Fellow

From: Ireland

Registered: 2004-07-21

Posts: 9,839

Re: how to find subnet and netmask?

skymt - no offense, but your masks are the wrong way around.

Gavenator, try subnet 10.0.0.0 netmask 255.0.0.0, or better still netmask 255.255.255.0 (I recommend this one, because I'm guessing you're unlikely to have 1677214 individual hosts on your network )

hacosta

Member

From: Mexico

Registered: 2006-10-22

Posts: 423

Re: how to find subnet and netmask?

no, he probably meant 255.0.0.0
**edit, tomk beat me to it

Last edited by hacosta (2008-05-24 20:44:31)

Gauvenator

Member

Registered: 2008-04-03

Posts: 172

Re: how to find subnet and netmask?

skymt - no offense, but your masks are the wrong way around.

Gavenator, try subnet 10.0.0.0 netmask 255.0.0.0, or better still netmask 255.255.255.0 (I recommend this one, because I'm guessing you're unlikely to have 1677214 individual hosts on your network )

thx that worked better.

but now I'm like OH NOES!!11 again because apparently I need a subnet declaration for wlan0.

setting up for thin clients is taking alot of work lol

WiLLiE

Member

From: Sweden

Registered: 2005-02-27

Posts: 135

Re: how to find subnet and netmask?

Why not put your new DHCP-server to use??
Gateway: 10.0.0.0
DNS: 10.0.0.0

If you want to do it manually, just increase the subnet.
So if you have 10.0.0.0 for your dns server, you could use 10.0.0.1 etc. Same netmask.