Loss of connectivity

[Pootytang]

Greetings all,

trying to figure out why I can't ping a computer from a computer on a different subnet unless I ping it from it's connected switch first. I can then ping from another subnet without issue for a time until the computer once again becomes unreachable after a period of inactivity. Connectivity can then again be re-established by pinging from the switch.

This is a multiple vlan/subnet network with switches connected in a star pattern from the core switch. Not a network expert and I'm guessing its something simple.

Thanks in advance!

Pootytang

[balaji.bandi]

 I ping it from it's connected switch first. I can then ping from another subnet without issue for a time until the computer once again becomes unreachable after a period of inactivity. Connectivity can then again be re-established by pinging from the switch.

This looks blizzard to me, 

You have not provided the environment and switch model what IOS running,

also show run , show IP route, show IP arp, show IP cef output  will help us to understand the issue.

what is the PC IP address and what gateway it configured, is this coming from DHCP ? where is the gateway located on the switch ?

[Pootytang]

Thanks BB,

There are no routes as there are no routers or routers on a stick. The switches hosting the PC's are direct connected to the core via vlan trunk. The source PC address is 192.168.16.13/20. The destination PC is 192.168.13.9/20. Gateways are 16.1 and 13.1 respectively which are vlan interfaces on the core. Hosts are each on a respective vlan. Sh ip cef on the switch hosting the destination pc shows its address as does the core. The core also shows the source PC address. The source PC's switch does not show it's address for the command. All three switches show 0.0.0.0/32 receive. The source PC is DHCP and the destination PC is static.

Pooty

[balaji.bandi]

i would ask again below information again :

You have not provided the environment and switch model what IOS running,

also show run , show IP route, show IP arp, show IP cef output  will help us to understand the issue.

[Pootytang]

Sorry BB,

the core is cat4500es8 v03.06.06.E. The target host switch is a C9200L v17.03.05, directly connected. Policy prevents me from posting show run info.

Pooty