Cisco to HP

I seem to be misunderstanding something in the configuration I'm working on. I have a flat network at the moment in the 10.0.0.x /24 range. They are connected via 3 cisco 2950's and 1 cisco 3560 (they are all on the default vlan 1).

Next to this rack is an HP 2900-48G that is separated into 3 vlans (vlan 5,6,7). They use the scopes 172.16.3.x, 4.x, 5.x. I have turned on inter-vlan routing (ip routing) and then setup a trunk port to connect to the cisco 3560. I can ping between the networks on the HP but I can' get any communication between the HP switch and the cisco switch.

I have verified that the trunk port has come up on both sides but I'm at a loss for why they can't communicate. I also tried on the HP switch, "ip route 10.0.0.0 255.255.255.0 10.0.0.23). 10.0.0.23 is the ip of vlan 1 on the cisco switch.

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Comments

networker050184

NightShade03 wrote: »

Ok thats what I thought I just wanted to make sure that I wasn't crazy. I gave up on the HP @ the moment. I moved over to using only a single cisco switch. I have a 3560 with two ports that I'm using. I have one in Vlan 1 and one in Vlan5 and for the life of me can't get them to talk to each other....

What configuration have you done?

You need to have IP routing turned on and create an SVI for each Vlan so the the switch can have connected routes for each subnet.

NightShade03

Just a basic config....there are other tings running on this switch which is part of our production environment so I'm trying to be really careful about making the changes outside these two ports.

ip routing
ip subnet-zero

interface Gigabit 0/10
switchport access vlan 5
switchport mode access

interface Vlan1
ip address 10.0.0.34 /24

interface Vlan5
ip address 10.0.5.254 /24

ip default-gateway 10.0.0.2

My client pc is plugged into int 0/10 with a static address of 10.0.5.3, gateway of 10.0.5.254. I can ping from the client to the gateway and can ping 10.0.0.34.....but nothing else in the 10.0.0.x scope.

mikej412

What do you get when you do a show ip route on the 3560? show ip interface brief? What does the arp table in the PC show? Can the other devices in the 10.0.0.x range ping the PC? Do you have any and all PC firewalls disabled? What's the security configuration on the other devices? Is there any type of security implemented in the 2560? Or is it pretty much just stock VLAN 1 blob?

NightShade03

mikej412 wrote: »

What do you get when you do a show ip route on the 3560? show ip interface brief? What does the arp table in the PC show? Can the other devices in the 10.0.0.x range ping the PC? Do you have any and all PC firewalls disabled? What's the security configuration on the other devices? Is there any type of security implemented in the 2560? Or is it pretty much just stock VLAN 1 blob?

Show IP Route:

10.0.0.0/24 Subnetted, 2 Subnets
C 10.0.0.0 is directly connected, Vlan 1
C 10.0.5.0 is directly connected, Vlan 5

Show ip int brief:

Vlan1 10.0.0.34 Yes NVRAM Up Up
Vlan5 10.0.5.254 Yes Manual Up Up
Gigabit unassigned Yes Unset Up Up

No other devices in the 10.0.0.x scope can ping the 10.0.5.x scope. This is just a Vlan1 blob network....all firewalls disabled, no security software, no switch or router has security in place.

networker050184

You need to think about it from a lower level. What are the 10.0.0.x hosts going to do when they need to send traffic off their local network?

They are going to send it to their default gateway, which you said is 10.0.0.1. That is the router, which has no idea what the 10.0.5.x network is (unless you put it on there, but you said you have no control on that so I'm guessing not). If you set the hosts gateway to 10.0.0.34 it looks like it should work fine as far as pinging each other.

mikej412

You're back to the routing issues for your current default gateway.

10.0.0.1 either needed to exchange routing information with the HP back when you were trying to trunk to the HP -- assuming you had a working trunk. Or you need to change the default gateway on the devices you're trying to ping to something that can route the packets.

Ah -- here it is....

mikej412 wrote: »

Well, if you're not changing the 10.0.0.x default gateway from 10.0.0.1, then 10.0.0.1 is going to have to exchange routing information with the HP switch -- and be able to redirect traffic for the other networks to the HP 10.0.0.x IP address.

While its a lot of work -- you may want to consider changing the default gateway on the 10.0.0.x network. This is a good example of the 5 P rule (or 6 P or 7 P rules depending on how many rude words you add in that start with P ) -- Proper Planning Prevents Poor Performance.

Are you going to do something different so we don't stay stuck in an infinite loop?

That 10.0.0.1 device is a vendor device? Can you get it configured to exchange routing information with your 3560 or HP? Can it send redirects to the PCs using it as a default gateway to go the the 3560?

NightShade03

@ networker - I don't know why but after reading your last post, the lights went off. I did some quick reconfigurations and some verification and boom everything just came up beautifully!

@ mike - I see your point and I'm trying to avoid contacting the company that hosts our router because everything with them is a week long process. I admit that if this network was thought out a little from the get go I wouldn't have such a headache trying to get things working now, however I guess that's just the breaks of IT.

Final Resolution:

Setup 5 Vlans on the HP, trunked it to the Cisco let the Cisco continue routing for the flat network. Changed the default gateway of the clients and things worked alot better. Thanks to all that helped, this has been a nightmare of a config....I'm not sure why I was overlooking things so much. I still don't care for the HP switches but until I become the boss its what I'm stuck with...

kristianbrown

Maybe im thinking too basic here. But if you enable cdp on both the cisco and the hp switch, do they see each other? Normally when I cant ping from 1 side to the other, it usually is a layer2 problem, not a layer3.

Just my 2 cent.

dynamik

kristianbrown wrote: »

Maybe im thinking too basic here. But if you enable cdp on both the cisco and the hp switch, do they see each other? Normally when I cant ping from 1 side to the other, it usually is a layer2 problem, not a layer3.

Or Layer 1

Do HP devices support CDP?

ColbyG

CDP is Cisco proprietary.

Cisco Discovery Protocol

kristianbrown

Aye, Im aware that CDP is Cisco proprietary..
I've had alot of HP switches who support CDP tho, so the protocol is used on other hardware producers also, probably licenced from Cisco.

ColbyG

That's interesting, I didn't know HP ever supported CDP. It looks like they stopped after Feb of 06, but still pretty cool that they used to.