TCP IP Subnet Mask Problem

[Brett Alan Logan]

Hi I am trying to set a subnet mask and IP address to a NIC on an L-2000 on an HP-UX 11.0 box. It won't accept the subnet mask below. If i set the subnet mask to the default it works fine...only with the subnet mask below it won't. I had the same problem about two months ago and the Support Line had me edit a file. I can't remember where this file is.

IP: 172.20.248.45
SubMask: 255.255.248.0

255.255.0.0 works fine but 255.255.248. will not.

Does anyone know the file i need to edit to enable this?

Thanks

[Steven Schweda]

> I am trying to set a subnet mask [...]

How, exactly?

> [...] It won't accept [...]

What, the keyboard locks up, or you get an
error message, or the command (whatever it
is) has no apparent effect, or what?

What did you do? What happened when you did
it?

[Brett Alan Logan]

I try to set it with SAM and also the network card is setup in /etc/rc.config.d/netconf.

When using sam I can set the IP and subnet mask then hit ok. If I use the 255.255.248.0 subnet mask the nic will set the IP at 0.0.0.0. If I use 255.255.255.0 or 255.255.0.0 the IP will set correctly.

I know there is a file to edit to enable me to use the 255.255.248.0 subnet mask but I don't remember it.

It had something to do with "Enable Multi Network" in the file...if I remember right.

[Brett Alan Logan]

Found it. Hope this helps someone in the future.

Please run the following command on the system:

1) Check the current value:
ndd -get /dev/ip ip_check_subnet_addr

2) Disable the subnet address check:
ndd -set /dev/ip ip_check_subnet_addr 0

Then we need to put these lines in /etc/rc.config.d/nddconf file:

TRANSPORT_NAME[0]=ip
NDD_NAME[0]=ip_check_subnet_addr
NDD_VALUE[0]=0

[Brett Alan Logan]

Found the solution