variable length subnets

[Ajay Sishodia]

Folks,

Does HP-UX networking supports "variable length subnets?"? I would like an HP CE to answer this among others. :)

[Berlene Herren]

Yes, there is a chapter devoted to Variable Length Subnetting in the LAN/9000 documentation

Berlene
(CE wannabee)

http://docs.hp.com/hpux/onlinedocs/B2355-90725/B2355-90725.html

[Ajay Sishodia]

Hi Berlene

Any Ideas on zero subnets? are they supported by HP-UX? I am using 11.00> I will assign points, don''t want the magic to appear just now :)

[Berlene Herren]

A subnet with all 1's or all 0's is a violation of RFC1122/1878. However, with the use of nettune (10.20) or ndd (11.0), you can disable the invalid subnet checking.

10.20
nettune -s ip_check_subnet_addr 0
11.0
ndd -set /dev/ip ip_check_subnet_addr 0

Regards,
Berlene

[Ajay Sishodia]

Berlene

Is this an example of subnet '0'?
IP address: 192.4.255.18
subnet mask: 255.255.255.192 ??
I think this is. Just need confirmation. I guess for that subnet mask the IP should be in the range of 192.4.255.65 - 192.4.255.126 ONLY right?

regards
Ajay

[Berlene Herren · Accepted solution]

Yes, the 255.255.255.192 results in the first two bits of each octet being set to all 1's - the same fax paux as all 0's.

Berlene