Configuring additonal server ports

[David Rodriguez]

Hi, if i'm using 2 server ports per chassis, and wish to add another 2, besides plugging in the cables and settings the ports on the interconnect for "Configure as Server Port" is there anything else that is needed and is there any disruption to traffic ?

[padramas · Accepted solution]

Hello David,

If the links between IOM and FI Server ports are individual links, then you need to acknowledge the chassis to initialize the new links. This will cause network disruption for few seconds.

We do not need to re-acknowledge the chassis If there is a fabric port channel between IOM and FI.

http://www.cisco.com/en/US/docs/unified_computing/ucs/sw/gui/config/guide/2.0/b_UCSM_GUI_Configuration_Guide_2_0_chapter_0101.html#concept_5D3D88341BFB43468B62B5A77876C67B

HTH

Padma

[David Rodriguez]

Thanks for your reply Padma, re-acknowledging the chassis reboots all the blades does it ?

What about changing from individual links to port-channel, will this require a re-acknowledgement as well ?

Using individual links what method does the FI use for sending traffic down 1 link as opposed to the other ?

[padramas]

Hello David,

Re-acknowledging the chassis does not reboot the blades. The links between IOM and FI are flapped and are included to carry traffic between blades and FI.

---->>>   What about changing from individual links to port-channel, will this require a re-acknowledgement as well ?

{Padma]  Depends upon where we make the change.

If you change it under Equipment > Policies > , you need to manually re-acknowledge the chassis for the links to form a port-channel.

If the global policy is set to None for " Link Grouping Preference " and we are changing the policy for specific chassis ( Equipment > Chassis X > Connectivity Policy "  to port-channel, then this configuration change automatically re-acknowledges the chassis. You will get a warning before saving the changes.

Fabric port channel is available when you have FI 62XX / IOM 220X / UCSM 2.0 hardware / software combination.

--->>>  Using individual links what method does the FI use for sending traffic down 1 link as opposed to the other ?

[Padma]  When using individual links between IOM and FI, traffic is distributed according to pre-defined configuration based on  number of physical links

Supported physical links are 1,2 4 and 8.

Let me know how your hardware model and current number of links used between IOM and FI.

Padma

[David Rodriguez]

thanks for the explanation

Our hardware/software is:

IOM - Cisco 2104XP

FI - Cisco 6120XP

Software - 2.0(1w)

Current number of links is 2, Global Policy Chassis Discovery Policy = 2 Link, Link Grouping Preferene = none.

[padramas]

Hello David,

The GEN I ( 6120 / 2104 )  hardware does not support port channel between IOM and FI.

Traffic distribution with

Two links

Link 1 -- Blade 1 3,5 and 7

Link 2 -- Blade 2,4,6 and 8

Once you add two more links and re-acknowledge the chassis,

Link 1 -- Blade 1 and 5

Link 2 -- Blade 2 and 6

Link 3 -- Blade 3 and 7

Link 4 -- Blade 4 and 8

HTH

Padma

[David Rodriguez]

Thanks Padma, that clears it up you answered my question. Much appreciated

[David Rodriguez]

Just in regards to re-acknowledging the chassis - if our blades contain vmware esxi hosts and we re-acknowledge the chassis, there is a 30 second pause, will all the vm's connected via fcp and nfs get disconnected or potentially power off ?

[padramas]

Hello David,

I do not have information on how much time ( seconds ) it wll take to complete re-initialization ( when we re-ack the chassis )  and whether this time period is higher than any protocol time out values.

I would suggest you to carry out this activity during maintenance window if servers are hosting critical apps on it.

Padma