How do you disable DCBX in LLDP?

[jonesl1]

We have been requested to turn off LLDP and DCBX in our Nexus 5k to be uses with some equallogic connections.  I was

able to get the lldp turned off, but the dcbx still shows enabled.   How do I get it to show disabled?

when I do the following show command, I keep getting the dcbx as showing YES.

sho lldp int e1/25

Interface Information:

  Enable (tx/rx/dcbx): N/N/Y    Port Mac address:

Here is what my port looks like:

interface Ethernet1/25

  description Connection to ISCSI

  no lldp transmit

  no lldp receive

  switchport access vlan xx

  spanning-tree port type edge

  flowcontrol receive on

  flowcontrol send on

How do I get dcbx off?

Thanks in advance!

[Robert Burns]

You might also need to diabled PFC (part of the DCBX stack):

priority-flow-control mode off

Then bounce the interface.

Regards,

Robert

[jonesl1]

I'm on a little older version.   4.2(1)N1(1).

my priority-flow-control mode is already off, even after a bounce of the interface it still seems to have same results.  

You thinking this might just be a version issue?

[Robert Burns]

Could be.  On my 5.x system it looks like this:

Software

  BIOS:      version 1.5.0

  loader:    version N/A

  kickstart: version 5.2(1)N1(2a)

  system:    version 5.2(1)N1(2a)

cae-sj-n5k-1(config)# show run int e1/3

interface Ethernet1/3

  no lldp transmit

  no lldp receive

  switchport mode trunk

cae-sj-n5k-1(config)# show lldp interface e1/3

Interface Information:

  Enable (tx/rx/dcbx): N/N/N    Port Mac address: 00:0d:ec:a3:aa:0a

Regards,

Robert

[vdsudame]

i see 'flowcontrol' being enabled on the port explicitly. probably thats why pfc is not taking effect. can you try the same test with 'flowcontrol' setting removed from the interface ?

Vinayak

[jonesl1]

I did what you suggested and made my port look like the following:

interface Ethernet1/25

  description Connection to ISCSI

  no lldp transmit

  no lldp receive

  switchport access vlan xx

  spanning-tree port type

I then tried againg to view the lldp on the interface.   This was the result:

Interface Information:

  Enable (tx/rx/dcbx): N/N/Y    Port Mac address:

Hasnt appeared to have changed.

I guess ultimately I just want to make sure it's not going to pass DCBX information on these ports.   Since LLDP is shut down, that should pretty much prevent dcbx from communicating right?

[Robert Burns · Accepted solution]

Correct.  It's showing it's "DCBX Capable" just not enabled.  You should be fine with no DCBX traffic on the interface.

Robert

[vdsudame · Accepted solution]

yes that is correct. At one time either PFC can be enabled or LLC. If you have LLC enabled, PFC will be disabled as such. So I would highly doubt even in your first case DCBX would have been negotiated even if it was showing enabled.

Thanks, Vinayak