NAT with 5400zl

[ozydave]

Just got a HP 5400ZL switch
My local authority has given me a single 10.120.160.0/22 subnet.
All network traffic that leaves to school must be on the 10.120.160.0/22 network
I wish to VLAN my network with 5 VLANs. I know each VLAN should have its own subnet range.
So is it possible to NAT the other subnets using the 5400zl so all network traffic looks like it fall within the range 10.120.160.0/22

Hope that make sense
Regards
Dave

[Patrick Terlisten · Accepted solution]

Hello Dave,

the 5400zl can't do NAT for you. If you want to use VLANs and the 10.120.160.0/22 subnet in each VLAN, you will get much more problems then you want. :) Try to use different ip subnets in the VLANs and route the traffic through a NAT device until it leaves the school network.

Best regards,
Patrick

[Pieter 't Hart]

"I wish to VLAN my network with 5 VLANs"

how many hosts must be in each vlan?
if you don't need 254 hosts in each subnet you can split your range in more than 5 subnet's.
/22= 4x/24 or 8x/25 or 1x/24 + 6x/25.

You (and your "local authority") may need to reconfigure the link between your 5400 and the "outside" to a smaller subnet (255.255.255.252 mask) with your 5400 as gateway for the whole /22 subnet.

[Pieter 't Hart]

read the last line of my post as /22 range (it's not subnet anymore in the suggested config).

[ozydave]

HI
Thanks for the reply.
2 of the subnets will be small (CCTV and fire alarm system). The other will need to be over 254. Maybe now we could get away with it but I would like forward plan for the extra capacity that will come.
Our LA control our Cisco layer 3 switch for outside connection. Trying to get the LA to possibly give us a larger address range or extra address ranges is so painful. My initial request to them was 20 July and their first response was 30 August! Thatâ s why I thought, if the 5400zl could NAT I could anything on our network which would be transparent to the LA.
Guess Iâ ll have to look at some routers. Any recommendations for HP routers

Regards
Dave