Still celebrating National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17

x
?
Solved

PC connected to a trunk port

Posted on 2014-12-22
4
Medium Priority
?
2,989 Views
Last Modified: 2014-12-22
I am just curious why when I plug my PC to a trunk port and it is working. In my network, vlan1 is for voice and vlan2 is for data. But the port that the PC connected to is a trunk. So if I guess correctly, the PC will be in the default vlan1 and that is why it is working. Correct?
0
Comment
Question by:leblanc
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
4 Comments
 
LVL 31

Accepted Solution

by:
Predrag earned 1000 total points
ID: 40513256
The reason that your PC is working is - native VLAN. Native VLAN has no VLAN tag.
So, all untagged traffic that acomes into switch port is considered as part of native VLAN (in your case VLAN1).
0
 
LVL 11

Assisted Solution

by:rharland2009
rharland2009 earned 1000 total points
ID: 40513261
Not necessarily. Many networks who share infrastructure for voice and data employ a strategy that allows the phones to be identified as such by DHCP options and given an appropriate address, after which they boot up into the appropriate VLAN.
For example, in one of our facilities we have VLAN 14 for computers and VLAN 8 for phones. Each port that a phone and computer connect to are untagged (native in Cisco-speak, I believe) in the computers VLAN and tagged in the voice VLAN.
Our VoIP phones have a 2-port switch for passthrough to the computer.
So what happens is this. The first time a phone is connected to the port, it powers up and asks for a DHCP address. We've configured the voice DHCP scope to pass some options (instructions) to the phones - in this case, reboot and come back up in VLAN 8. The computers ignore these options and will get a DHCP address as normal since their VLAN is the 'default' for this port.
0
 
LVL 1

Author Comment

by:leblanc
ID: 40513277
I assume that your phones are connected to ports configured with voice and data vlan. With my phones (NEC), it is a bit wired because my ports have to be configured as a trunk.
0
 
LVL 31

Expert Comment

by:Predrag
ID: 40513290
As I told you.
Trunk is created, but only voice traffic is tagged.
PC VLAN traffic is not tagged, so all untagged traffic is considered as part of native VLAN.
If you change native VLAN to VLAN 10, all untagged traffic will be part of VLAN 10 in that case.
0

Featured Post

Understanding Web Applications

Without even knowing it, most of us are using web applications on a daily basis. Gmail and Yahoo email, Twitter, Facebook, and eBay are used by most of us daily—and they are web applications. We often confuse these web applications tools for websites.  So, what is the difference?

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

I had an issue with InstallShield not being able to use Computer Browser service on Windows Server 2012. Here is the solution I found.
WARNING:   If you follow the instructions here, you will wipe out your VTP and VLAN configurations.  Make sure you have backed up your switch!!! I recently had some issues with a few low-end Cisco routers (RV325) and I opened a case with Cisco TA…
In this video we outline the Physical Segments view of NetCrunch network monitor. By following this brief how-to video, you will be able to learn how NetCrunch visualizes your network, how granular is the information collected, as well as where to f…
Michael from AdRem Software outlines event notifications and Automatic Corrective Actions in network monitoring. Automatic Corrective Actions are scripts, which can automatically run upon discovery of a certain undesirable condition in your network.…
Suggested Courses

721 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question