HP 3800 Basic VLAN IP Routing Solution

[andrewwong2000]

Hi, 

After days of trial and error, and reading posts about setting up my HP 3800 to do IP routing across multiple VLANs, and not having much success (OS KA16.04.0019), I thought I'd share what actually worked.

Many articles/google posts mentioned in the config:

i. ip route 0.0.0.0/0 192.168.1.1    -- default route 
ii. ip routing -- switch on ip routing
iii. For VLAN 10,  ip address 192.168.1.2 255.255.255.0
iv. Say VLAN 20, ip address 192.168.2.1 255.255.255.0

This would get the interfaces up, and you could ping them from the same subnet.
eg. ping 192.168.1.1 from 192.168.1.2, ping 192.168.2.1 from 192.168.1.2,  ping 192.168.2.1 from 192.168.1.1.

But anything on 192.168.2 would not have packets forwarded at all.

So the missing config was to enable rip or ospf. Static routes didn't work.

eg. for each VLAN interface:

VLAN 10 config add ip rip 192.168.1.2,
VLAN20 config add ip rip 192.168.2.1

[parnassus]

Hi @andrewwong2000, let me put aside for a moment the RIP approach.

Few questions:

1. Are hosts addressed within VLAN 20 (192.168.2.0/24, SVI interface 192.168.2.1) using the SVI as their default gateway?
2. Are hosts addressed within VLAN 20 using OS Firewall/Antivirus potentially interfering with proper packets egressing/ingressing flows to VLAN 10 or any other (non local) networks?
3. What to you mean with "But anything on 192.168.2 would not have packets forwarded at all."?

Based on your described scenario I expect that:

1. Inter-VLAN routing works (in absence of any ACL): any host on VLAN 10 is able to connect to any host on VLAN 20 and vice-versa (clearly hosts need to be properly addressed and access ports need to be properly configured in terms of VLAN tagging, actually untagging into VLAN 10 or VLAN 20).
2. Routing to ANY other non local connected networks (so ANY network which is not 192.168.2.0/24 or 192.168.1.0/24) will be routed toNext Hop Gateway 192.168.1.1 by means of Route of Last Resort (destination 0.0.0.0 mask 0.0.0.0 via 192.168.1.1).
3. Next Hop Gateway (is properly addressed and VLAN tagged, actually untagged on VLAN 10) should then forward to its other interface to external networks.
4. Next Hop Gateway should understand how to route back to VLAN 20 through a static route (destination 192.168.2.0 mask 255.255.255.0 via 192.168.1.2)

Does that sound reasonable as approach?

[-Alex-]

Hello andrewwong2000,

If you need static routing only you should have the route to 192.168.2.0 network on your gateway which should lead to  192.168.1.2.where it can reach 192.168.2.x network. 

Also between the networks if for vlan 10 the default gateway is not the switch but the default gateway 192.168.1.1 this is also a reason why 192.168.1.x may not be able to reach VLAN20 devices.

Hope this helps.