If switchport mode trunk command allows multiple vlan on same interface, then what is the need of switchport trunk allowed vlan all command?
Switchport mode trunk - allows all the VLAN
switchport trunk allowed vlan XX ( means only allowed VLAN in the list) ALL means again all the VLANs
So you mean both are doing same function, Right? Then why we need two separate command for same function?
Magesh Kumar G
those options (add, remove, all, etc) are sort tricky a bit. I had same issues.
true, switchport mode trunk allows all vlans by default. but if u make some changes, vlans list of allowed vlan x is displayed,
so, switchport trunk allowed vlan all command can be use after any previous manual manipulation to go back quickly to default settings, aka allowing all vlans
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You don't have to configure switchport trunk allowed vlan all. By default a trunk interface trust all VLANs, but if you have changed it manually to only allow specific VLAN(s) then you can change it back to all VLANs by this command