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Interconnect between Cisco 2821 & HP 5412zl

I've just acquired a new network and having some trouble managing  some servers/switches across the interconnect and looking for some help.

I  have a 5412zl 10.215.x.x/16 Most of the connections on this switch are  on vlan1. B9 is the port which is connected to a Cisco 2821 Router. The  port on that end is GE0/1. The port on the cisco side is not a trunk but  configure with an ip of

Its part of a some ip  access group. The network that i now sit on is a 172.x.x.x/24 (behind  cisco router, about 3 hops to that main 2821)

We current  have a system on my side that talks to a server on the 10.215. that has  no issues. I'm trying to access some switches on the 10.215. and have  had no luck reaching them.

Here is the access list that i found that port is configured to use:

permit ip
permit ip
permit ip
permit ip
permit ip
permit ip
permit ip
permit ip

I  would think the first permit would allow me to get through to the  10.215 side but maybe i need to set something up on the hp size to let  it know how to get back? I'm very new to this stuff.

Thank you!!

Everyone's tags (5)
VIP Super Bronze

Interconnect between Cisco 2821 & HP 5412zl

If you are trying to access the HP switches, they need to have a management IP address configured.on them.

are the HP switches layer-2 only. Are all the hosts sitting behind the HP switches are part of the same subnet as the 2821 (

It would be helpful, if you can provide a diagram.


Community Member

Interconnect between Cisco 2821 & HP 5412zl

The Hp switch the cisco 2821 is plugged into is a 5412zl which is a layer 3. everything behind the hp switch is /16 one flat. vlans aren't really used etc.

Community Member

Re: Interconnect between Cisco 2821 & HP 5412zl

This is still an issue:

Network A - Cisco - mainly all 172 network..but we have others. that side handles 10.10., 192.168. Network in question. On this router only 4 network interfaces i believe. one interface has as ip applied to it. i was told that everything from the 10.215.x.x/16 side goes through that connection to see stuff over on 172.x.x.x side. Everything from an application and user perspective is working and has been working for about 5 years. Now that i'm managing Network A and B...I cannot manage switches on network B from network A.

Network B - Hp - Only 10.215.x.x. All the devices on this network have a gateway of (checkpoint firewall). the port of the 5412zl that connects to the cisco there's no ip assignment, just a regular switch port.

Every gateway on the Network B side and including the port configured on the Cisco 2821 switch is the checkpoint firewall.

Everything (95%) on the Network B is on the default Vlan, i know this is bad and i'm going to be changing that.

From Network A i can see computers and servers on the 10.215. /16 side. Normally they're 10.215.2.x-10.215.99.x. I cannot ping, ssh, or telnet into anything /16

All switches on network B are configured with a gateway of the firewall.


1. I need to be able to manage Network B's switches from a Network A admin machine.

2. I have a monitoring server on the network B side that needs to monitor network A's devices.

3. Why is the port on the Cisco side setup with a /24 when my network A is a /16? ( more like a question)


1. Am i missing a route in there?

2. Is there an ACL that is blocking that traffic?

I'm attempting to attach a diagram layout of my situation along with the running-config files from both switches.

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