Re: Inter-Vlan Routing Issue - Page 2

amatorjnr · ‎04-09-2021

I have this weird problem I'm facing on my network.

I have inherited an inter-vlan configuration with a layer 3 switch and everything works out fine.

Recently I had to add a new server to the network and I've noticed something weird.

All computers are on a different vlan and can communicate with each other and other servers.

example. PC = Vlan 2

Servers= vlan 3

New Server = vlan 4

everything works, pings go through all vlans.

BUT

After a while, both PC's and Servers on Vlan 2 and 3 can't ping New Server on Vlan 4.

Until

1. after i disconnect new server network cable and reconnect it,

2. or shutdown and renable port New Server is connected to

3. or i log in to the layer 3 switch and ping New Server

4. or I use a computer on vlan 4 to ping New Server.

AFter performing any of the options 1-4. All other host can ping New Server again for a while, then it stops.

I've noticed so far that until I'm continously pinging NEw Server, pings from all other vlans stop going through.

what could be the cause.

PS. New Server port = Access

Inter-vlan routing works

I've changed network cable twice

switch doesn't show any errors on interface

amatorjnr · ‎05-14-2021

same issue. It works for a while then stops

amatorjnr · ‎05-14-2021

Sorry I haven't replied here in a while. I'm not so sure but I think it has to do with a native vlan.

I think the problem is a layer 2 issue.

Every time I clear arp, it works for a while. then it's like the switch somehow forgets how to get to that addess till i ping directly from a pc in the same vlan or from the core switch to that server. then Boom, it starts working again.

I think it's a native Vlan issue because as I said early, its an infrastructure i came to meet so i dont want to change things up in a production environment but there isnt a specific vlan dedicated as a native vlan even though vlan 1 is disabled on all switches. instead, the data vlan on every block is used as native vlan(which seems very weird. I tried changing that, and the cisco phones connected stopped working).