Dwilliam62 THANK YOU!

I disabled DCB and the warning is gone.

Rafko

Hi Don, 

Thanks, The DCB disabling solution works but still the options DCB/VLAN id seems to be applicable to all interfaces as it is group level settings. 

Is there any possibility to disable DCB for selected ethernet interface ?

does this warning is applicable to management interface also ?

Thanks & Regds,

Bala 

Don, we get the same message after upgrading EQL firmware from 5.2.5 to 6.0.1, but we're using M8024-k switches - those should be fully DCB compliant or?

Or will that message disappear after correctly configuring DCB on the switch?

You can see if show recentevents on your EQL returns

1022:41:QRQ:23-Nov-2012 14:20:20.155416:dcb.c:1871:WARNING::9.3.0:Interface eth0 has negotiated DCB priority flow control with the switch. However, the switch did not configure iSCSI traffic for a lossless priority. No Ethernet flow control is enabled for iSCSI on this interface.

To fix it configure flow control manually or change interface to auto-up and allow your storage to configure it.

Setting M8024-k interface to "lldp dcbx port-role auto-up" solved the problem for me.

So how could you explain this message:

806:311:EQL6110-1:SP:23-Nov-2012 15:54:12.021766:emm.c:2501:INFO:28.2.131:Ethernet flow control is now enabled on all interfaces.

BTW: I have the newest image (5.0.1.3) installed on the switch.

I've double checked it and it seems to be totally non deterministic. My solution works for one eql storage and doesn't work for another. Both arrays have same firmware revision and are connected to same stacked switches with identically configured ports and only one reports problem.

So probably I'll have to disable DCB which is not the best solution :-/

Thank you so much!!! This helped me a lot. I am seeing the warning many days ago.

Please tell me if i upgrade the eql firmware then, is there any performance issue with I/O reads & writes?

Hi Dell-Donald Wi,

I have been tasked with turning off dcb on a port of a Dell 8024k switch. Could you give me a step-by step guide on how to do it via CLI?

Thank you!

Additional info that may help:

1.  DCB will automatically be disabled if you disable LLDP.  This is because DCB parameters are communicated via LLDP packets.  So if you turn off LLDP, it will turn off DCB as well.  Since many environments use LLDP, turning off LLDP is not an option.

2.  Edge devices like NICs and storage devices are in "willing mode", meaning they always inherit DCB parameters from a source switch.  So if you want to completely disable DCB in your network, you turn it off on the switch.   Some edge devices allow you to disable DCB, usually via the option ROM.

3.  It's not good practice to disable DCB on one edge device (i.e. EQL) and leave it enabled at the other end point (i.e. server NIC).  This causes flow control incompatibilities.

4.  On the PC8024, you can try to disable DCB on the interface itself via the following commands:

no lldp tlv-select dcbxp ets-config

no lldp tlv-select dcbxp ets-recommend

no lldp tlv-select dcbxp pfc

no lldp tlv-select dcbxp application-priority

Also, be sure to disable DCB globally via the "no dcb enable" command.

Thank you for your reply. The problem is that I am unable turn it off globally because there is no such command, I have tried everything so far in vain.

Show version command prints the following:

show ver

System Description................ Dell Ethernet Switch
-omitted for brevity-
System Model ID................... PCM8024-k
Machine Type...................... PowerConnect M8024-k

unit image1      image2      current-active next-active
---- ----------- ----------- -------------- --------------
1    5.0.1.3     5.1.0.1     image2         image2

I was unable to turn lldp off, either because there is nosuch command either.

(config-if-Te1/0/9)#?

description              Add Description to the interface
do                       Run Privileged Exec mode commands.
dot1x                    Configure Dot1x interface commands.
exit                     To exit from the mode.
show                     Show configured settings and operational status.
shutdown                 Enable/Disable a port.

I don't know what the problem could be.