Avatar of molly22
molly22 asked on

VLan issues

I have a strange issue, I hope someone can help. I hope I can explain it well enough.
I have a 4500 3com switch that I created a vlan and a vlan interface on. The switch has one port associated to the vlan as port access. I have a device plugged into that port and the device has a static ip with subnet and gateway set.
The 4500 switch connects directly to my router which is a 3Com 5500 switch by fiber. The uplinks are set as trunk ports. I have same vlan set on 5500 with an interface set as the gateway for this vlan. I also have the OSPF route set for the vlan.
The issue is; I can ping the switch and the device from the 4500 switch and the 5500 router, but I cannot ping the device from any other switch at that location or over my network. I can ping the interface on the 4500 switch from any location, but I cannot ping the device.

Why can I see the device from the router but not over the network?
Why can I see the switch from any location but not the device?
Network ArchitectureNetwork Management

Avatar of undefined
Last Comment

8/22/2022 - Mon
Mohammed Khawaja

All other devices connected to other switches must be tagged with the same VLAN or have routes configured between the VLANs so that switch knows how to forward the request.

Is this device set with the proper subnet/gateway? Are you tagging the port the device is connected to with the appropriate VLAN tag?

The port that the device is plugged into is set as port access because it is to see only that vlan. Uplink on swtich and router are trunk port passing all vlans.

If my router can see the switch and the device and I can see the switch over the network why can I not see the device?
Experts Exchange has (a) saved my job multiple times, (b) saved me hours, days, and even weeks of work, and often (c) makes me look like a superhero! This place is MAGIC!
Walt Forbes

How about the first question. Does the device has the proper subnet/gateway?
Mohammed Khawaja

Even if you have a trunk port, you still have to define which VLANs you allow through the trunk as shown in an example for a Cisco device:

interface Port-channel1
 switchport trunk encapsulation dot1q
 switchport trunk allowed vlan 2,10,20,30,50,60,100,999
 switchport mode trunk
 spanning-tree link-type point-to-point
 hold-queue 150 out

Log in or sign up to see answer
Become an EE member today7-DAY FREE TRIAL
Members can start a 7-Day Free trial then enjoy unlimited access to the platform
Sign up - Free for 7 days
Learn why we charge membership fees
We get it - no one likes a content blocker. Take one extra minute and find out why we block content.
See how we're fighting big data
Not exactly the question you had in mind?
Sign up for an EE membership and get your own personalized solution. With an EE membership, you can ask unlimited troubleshooting, research, or opinion questions.
ask a question

Subnet issue on device.
Get an unlimited membership to EE for less than $4 a week.
Unlimited question asking, solutions, articles and more.