I think the number of hosts in a subnet should be 2^n, So it can not be 191 or 192. Jiangbo Li > -----Original Message----- > From: linux-net-owner@vger.kernel.org > [mailto:linux-net-owner@vger.kernel.org] On Behalf Of Frank Brodbeck > Sent: Wednesday, April 09, 2003 1:19 PM > To: linux-net@vger.kernel.org > Subject: vlsm subnetting > > > Hi list, > > I'm stucked here with variable length subnet masks. > > Well I've gone through the rfc1878, googled a bit around, read through > the TCP/IP Networking Administration by Craig Hunt (okay I > must confess > it's ``just" the german translation) and read a pile of eMails in your > list's archive with no result except that I'm confused... > > Here's the detail: > > I'm having here a class C network which I want to split into unequal > parts. Starting point is 172.25.156.0/24 > Well I just thought *no problem* and started to split the whole net > via vlsm into the following parts: > > net broadcast hosts range mask* > 172.25.156.0 172.25.156.192 1-191 255.255.255.0 > 172.25.156.193 172.25.156.223 194-222 255.255.255.192 > 172.25.156.224 172.25.156.239 225-238 255.255.255.224 > 172.25.156.240 172.25.156.255 241-254 255.255.255.240 > ------------ > (*) I'm pretty sure that this is completely rubbish but see it as a > symbol of my confusion > > I guess I got the part, that a vlsm of 255.255.255.128 would divide my > class C into two subnets of each 126 hosts and that a vlsm of > 255.255.255.192 would do the same with 4 subnets each with a max. of > 62 hosts. > > So if somebody could mind and bring some light in here I'd be > thankful. > > HAND > Frank. > -- > Frank Brodbeck System administrator apprentice > oakenshield@gmx.net University of Karlsruhe > - > : send the line "unsubscribe > linux-net" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
