Aleksey Naumov <[EMAIL PROTECTED]> wrote:
> Pierre,
>
> here's my "route -n" output:
>
> [root@botik /root]# route -n
> Kernel IP routing table
> Destination Gateway Genmask Flags Metric Ref Use Iface
> 136.183.128.0 0.0.0.0 255.255.224.0 U 0 0 0 eth0
> 127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
> 0.0.0.0 136.183.129.253 0.0.0.0 UG 0 0 0 eth0
>
> Here's the setup for my machine I got from our sys admins:
> IP: 136.183.132.47
> Subnet: 255.255.224.0
> gateway is 136.183.129.253
>
> I am confused why there is a destination network 136.183.128.0 in my table, and
> not
> a 136.183.132.0. Does this make sense?
Well, lets do some hex and decimal arithmetic.
132 (octet 3 of your ip addr) is 128 + 4, or 0x84
224 (octet 3 of your netmask) is (hex calc) 0xe0
So, to find what subnet you are on, and your ip addr with ff.ff.e0.00,
so 136.183.132.47 (88.b7.84.2f) bitwise anded with ff.ff.e0.00 equals
88.b7.80.2f, or 136.183.128.0 - which gives your subnet.
Hopefully this is what you want, because its what has been specified
by that netmask ;-)
If you want the subnet to be 136.183.132.0, then the netmask must be
255.255.255.0 (ff.ff.ff.0).
Clear as mud? As mentioned earlier by someone else in reply to one of
my emails - there are some good documents in the howtos about netmasks
and such. If all this blather does not help (or confuses!), then I'd
suggest either a search with your favourite search engine, or go find
that message that referenced the howtos and then go look at those
howtos... They really are good, I've read them ;-)
rc
Rusty Carruth Email: [EMAIL PROTECTED] or [EMAIL PROTECTED]
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