Does vCon Placement represent physical "DCE" to "Backplane Port" of IO Module connection?

[rumak18]

Hi,

When configuring vNIC/vHBA Placement in Server Profiles, i can see that we have four vCon available.

Does this number represent my DCE to Backplane Port connecton which can be seen in "Hybrid Display" under "Chassis"?

Because here i see four lanes going out from a blade server to my two IO modules (2x2=4).

See also attached file.

[mojafri]

Hi @rumak18,

VCON is virtual representation of physical adapter on the server. VCon is a stateless, logical component that enables this provisioning in platform-independent manner & at the same time provides enough tools to the user to control the placement of virtual devices.

With VCons user is able to:
1.    Create vNICs/vHBAs without much knowledge of PCIe adapter cards present in the server. System should do the validation and report configuration failure if the configuration is not supported. 
2.    Maintain consistent and accurate vNIC/vHBA PCIe orders across system upgrades.    
3.    Move service profiles across different type of platforms and maintain similar relative vNIC/vHBA PCIe ordering.

UCSM currently supports 4 VCons (You will always see this) that are statically created by the system, independent of the server’s PCIe slot layout. These 4 VCons in turn get mapped to physically present adapter cards upon server association. Adapter ID for VCON placement is assigned during blade discovery and depends on PCI device enumeration order. 

You can have multiple DCE interfaces depends upon adapter & IOM combination you have. (Its just a connection between backplane & adapter-port), nothing related to vcons.

More under: https://www.cisco.com/c/en/us/td/docs/unified_computing/ucs/ucs-manager/GUI-User-Guides/Server-Mgmt/3-1/b_Cisco_UCS_Manager_Server_Mgmt_Guide_3_1/server_related_policies.html (Search with "vNIC/vHBA Placement Policy Settings")

Please rate if you find it helpful. 

Regards,

MJ

[rumak18]

VCON is virtual representation of physical adapter on the server.

But my servers don't have any PCI adapters physically don't they? They only adapters we have are the VIC1240 and here i thought the card resides in the chassis doesn't it? Or do i have a VIC1240 in EVERY blade server?

As we have blad servers i thought that the only "adapters" they have is the connection from DCE ports to backplane ports of the IOMs.

[mojafri]

But my servers don't have any PCI adapters physically don't they? They only adapters we have are the VIC1240 and here i thought the card resides in the chassis doesn't it? Or do i have a VIC1240 in EVERY blade server?

Yes, every blade has adapters, else it won't even discover in UCSM. Please check the below links to have a physical view: 

https://www.cisco.com/c/en/us/td/docs/unified_computing/ucs/hw/blade-servers/B200M4/B200M4_chapter_011.html#ID902

https://www.youtube.com/watch?v=H6mcvsN8dbg

Regards,

MJ

[rumak18]

1.Ok, so for now i've checked my adapters under "Equipment\Chassis\Chassis1\Servers\Server1" and "Inventory\Adapters".

Here i see "UCSB-MLOM-40G-01". So thow this adapter adopt to vCON adapters?? As i have four vCONs...which one belongs to my MLOM adapter?

2. And how does it look with a "UCSB-MLOM-40G-01" and a second one like "VIC 1280".  I can add two more adapters additionally to these two? I'm asking because i wrote some articles about UCS but there is mostly a combination of these two...and no one other. 

[mojafri · Accepted solution]

1.Ok, so for now i've checked my adapters under "Equipment\Chassis\Chassis1\Servers\Server1" and "Inventory\Adapters".

Here i see "UCSB-MLOM-40G-01". So thow this adapter adopt to vCON adapters?? As i have four vCONs...which one belongs to my MLOM adapter?

• In a server with 1 pcie adaptor card, all the 4 VCons point to the same adaptor card.
• In a server with 2 pcie adaptor cards, VCon-1 and VCon-3 point to adaptor-1, VCon-2 and VCon-4 point to adaptor-2.
• With 3 pcie cards, VCon-1, VCon-2 and VCon-3 points to the corresponding adaptors 1, 2 and 3. VCon-4 points to adaptor-2.
• With 4 pcie cards, VCon-1, 2, 3, and 4 points to adaptors 1, 2, 3 and 4 in order.

2. And how does it look with a "UCSB-MLOM-40G-01" and a second one like "VIC 1280".  I can add two more adapters additionally to these two? I'm asking because i wrote some articles about UCS but there is mostly a combination of these two...and no one other. 

Depends on blade/rack-server model. Half-width can have 2 adapters, however full-width could have 3 adapters. 

Don't forget to mark answers as correct if it solves your problem. This helps others find the correct answer if they search for the same problem.

Regards,

MJ

[rumak18]

Hi majafri,

really very helpful. Thank you.

To complete this topic... where do you have these informations about vCon affiliation?

And

you say

Depends on blade/rack-server model. Half-width can have 2 adapters, however full-width could have 3 adapters. 

So how or when is it possible to have four adapters?

[mojafri]

@rumak18,

More can be found here: https://www.cisco.com/c/en/us/td/docs/unified_computing/ucs/sw/gui/config/guide/2-2/b_UCSM_GUI_Configuration_Guide_2_2/configuring_server_related_policies.html#d79727e13282a1635

https://www.cisco.com/c/en/us/support/docs/servers-unified-computing/ucs-b-series-blade-servers/112000-virtual-interface-adapter-00.html#topic2  <<<< but very old >>> 

So how or when is it possible to have four adapters? In rack-servers.

Regards,

MJ

[rumak18]

Hi Mojafri,

I see.... ok.

First...thank you so much! You really opened my mind in some cases i just would not learn on my own as long as i don't lay my handys on the physical servers. We just have remote access to them.

Now i've read the whole thread once again and still got a question : DO the MLOM and VIC PCIE Adapters have a network port (like for Ethernet or Optical Fibre cables) or is this connection just an internal connection to the chassis?

[mojafri]

Hi @rumak18,

Glad i was able to help. Yes, you can't see physical ports like switch in blade server, however in rack-server you will. For blades, it just have latch which connects on back-plane. 

Regards,

MJ