Switchport access removed.

[mohdashraf]

Hi all,

I have a switch SG500 28G POE stackable. See my config below in my switch and this is the corect configuration with no issue.

interface gigabitethernet1/1/2
 description Dlink-SW-GSD-4-IPphones-No5
 switchport trunk allowed vlan add 20,440

This port has been used for iphone for vlan 20 and 440. Suddenly just when the issue comes, iphone cannot be used and i check the configuration as shown below.

interface gigabitethernet1/1/2
 description Dlink-SW-GSD-4-IPphones-No5

Looks like it has been deleted automatically. If you have any idea why this occue it would much appreaciated.

Regards,

Ashraf

[mohdashraf]

Update: I added it back to this interface same configuration and write memory. Its still occur this issue.

Hope this will be more clear description.

Thank you.

Regards,

Ashraf

[Jonn cos]

Try the following commands

interface gigabitethernet1/1/2

description Dlink-SW-GSD-4-IPphones-No5

switchport mode trunk

switchport trunk native vlan id (just to be on safe side)

switchport trunk allowed vlan add 20,440

[Tom Watts · Accepted solution]

Hi Mohd, if the configuration is 'disappearing' it is probably because the smart ports over write your configuration which is the likely result you have an upstream device advertising something different.

-Tom
Please mark answered for helpful posts

[mohdashraf]

Hi Tom,

Bravo. I tried to disable smartport for port gigabitethernet1/1/2 for 3 days and it works.

Thanks a lot.

-ashraf