[lug] Cisco 675 Config.

Sean Reifschneider jafo at tummy.com
Tue Sep 5 15:48:31 MDT 2000

On Tue, Sep 05, 2000 at 01:20:11PM -0400, John Starkey wrote:
>So with 4 machines 5 IPs is all that's needed (not MASQ'ing)? If my IP's
>are x.x.x.0/4 with:
>0 PTR (Cisco 675)

All bits set to zero in your subnet is always the network address, you can't
assign that to a piece of equipment.  In a /29, you would have:

	network + 0 == Network IP
	network + 1 == Usable IP
	network + 2 == Usable IP
	network + 3 == Usable IP
	network + 4 == Usable IP
	network + 5 == Usable IP
	network + 6 == Gateway IP
	network + 7 == Broadcast

Usually the gateway is broadcast - 1, but some folks use network + 1...
The RFCs prefer the former though.

>1 PTR ns
>2 PTR ns1
>2 PTR www
>3 PTR mail
>4 PTR imac
>for instance.
>Will this work???

Not if your default gateway is on 0.

>How do machines on the outside know where x.x.x.1 is when I change my
>SOA to that number???

If you mean, how would outside machines know where your primary name
server is, that's found through WHOIS.  If you mean "how do they reach
*.1", they do it via internet routing magic, just like they reach every
other IP.

>Is there a routing table in the 675??


 Use more honey!  Find out what she knows.
                 -- _Buckaroo_Banzai_
Sean Reifschneider, Inimitably Superfluous <jafo at tummy.com>
tummy.com - Linux Consulting since 1995. Qmail, KRUD, Firewalls, Python

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