3750E switch coudnot ping a video conferencing system

[mestasew1]

I am working  on a cisco switch  model 3750 E on ios  ver 12.2 and installing a newly purchased VC device configured with static address under the vlan created for video. After setting  subset mask and GW  on the device , a ping to the device failed.  the vlan interface is up and the link to the device is configured as access to the vlan.  I was able to see the device mac  and  ip address on the mac , arp table. I have tried various settings on the link such as trunk and dynamic desirable which does not help. also verified there is no any acl blocking the traffic.

I sent broadcast traffic to the vlan from its DG , but no response from the device nor can I ping the switch from the device.

I have started working with the techs from the device provider. but I also want to present the  problem for Cisco community to see any suggestion or share  experience on  such situation.

Best regards

[Georg Pauwen]

Hello,

post the config of the switch.

Do you have 'ip routing' enabled globally ?

[mestasew1]

Yes, IP routing is enabled. What part of the switch config you are interested to look into ?

[Georg Pauwen]

Hello,

where are you pinging from ?

Basically, your switch configuration should look like this:

interface FastEthernet0/0
 description VC Device Video
 switchport access vlan 10
 spanning-tree portfast

interface Vlan10
 ip address 192.168.10.1 255.255.255.0

[mestasew1]

Georg,

I thank you for your response to my post.

the interface and van configuration are the same with the one you posted.

I have tried to ping the device ip which configured as 192.168.10.5/24 from the switch int vlan add 192.168.10.1.

I have also triedto ping  the vlan int add 192.168.10.1 from the device 192.168.10.5 

the puzzle is I see the device mac and ip add, and port  in the switch arp and mac  table. but the ping fails.

.

[Georg Pauwen]

Where are you pinging from ? What is the IP address of the device you are pinging from ?

[mestasew1]

ping from (Source interface ) 192.168.10.1

ping destination 192.168.10.5--- this is the device address

also used broadcast address 255.255.255.255 from the vlan interface 192.168.10.1

I used extended ping to do so.

[Georg Pauwen]

Hello,

what is the VC device, is that a Windows device ? Can you display the IP configuration of that device (e.g. 'ipconfig /all) ?

[mestasew1]

the device configuration can be viewed via web interface I set it manually

Ip add   192.168.10.5

subnet 255.255.255.0

defualt gateway 192.168.10.1

the dns info are not that important at this level.

[Predrag Jovic]

Please, make sure that SVI for VLAN 10 is in up up state.

sh ip int brief

Also, if switch if VTP client mode VLAN 10 will not be added when port is assigned to VLAN 10, VLAN must be created on VTP server. Check if VLAN 10 is present on switch.

show vlan brief

show spanning-tree vlan 10

[mestasew1]

The vlan is working fine and it is in up up state.let me put the question in another way.

If the switch has learned the mac and if address of a device , why the ping test fail ? There no acl blocking the traffic.

[Georg Pauwen]

What device is that ? Is that a Windows machine ? Could it be that ICMP (Ping) is somehow disabled on the machine (by an internal firewall or anti virus software) ?

[mestasew1]

Georg,

the device is a polycom VC system. the sytsem use ip h323 protocol for video call. there are few settings to enable/ disable ports, one of which enables icmp responses as unreachable.

so when i ping from the device to the switch I get h323 is no reachable.

[Georg Pauwen]

Hello,

can you, for testing purposes, connect your laptop to the switchport the VC device is connected to now, assign it the same IP address and gateway, and ping ? If the ping works, you know it is a setting on the VC device...

[mestasew1]

Ya, I have already did that and the ping successed. 

One more thing I did which add to my puzzle, when I connect the device to a laptop and ping the device ...the device responds. That suggests the problem is between the device and the swich.