BladeSystem - General
1748204 Members
3197 Online
108759 Solutions
New Discussion

Re: is Virtual Connect stacking required?

 
Bob_Vance
Esteemed Contributor

Re: is Virtual Connect stacking required?

BTW,
I was able to imagine a design wherein the VCM on VC1 *could*, *theoretically*, know about the other VCs via the management network and the OA, which could communicate the VC arrangement to all the VCs.

So, that's how I came up with "no stacking required."
But, absent a "Theory of Operation" document ...


Pyscho's new scenario seemed to imply setting up the domain with stack-links and then breaking the stacking.

I'm wondering about just having two, mutually unaware domains from the get go.

Primary VCM in VC1 and another Primary VCM in VC3.

The OA mgt page probably would only have a link for the VC1 VCM, but we could connect directly to VC3 which should be running VCM, since it doesn't know about VC1,2


But still worried about the profiles.
I'm not even sure how the profiles get applied.
Thru the ILO?


bv

"The lyf so short, the craft so long to lerne." - Chaucer
Bart_Heungens
Honored Contributor

Re: is Virtual Connect stacking required?

Mmm not really sure about what is mentioned above...

 

If there are no stacking links vertically the VCM running on modules 1 and 2 cannot communicate with the others and cannot configure them? Sorry but this is not true...

 

Simple example: how do U explain that in slot 3 and 4 are FC VC modules? There is no stacking possible between FC and Ethernet and yes U can configure them.

 

I have 27 enclosures at my customer site with 6 VC modules: 4 ethernet in 1, 2, 5 and 6 and FC modules in 3 and 4.

 

Without the stacking cables between 1 and 5 and another one between 2 and 6, I can configure all 6 modules... For VCM this is 1 VC domain...

 

Only: without the stacking cables U will get an error stating that this is not an ideal situation... Because with VC I can perfectly say that the onboard NIC 1 (physically connected to module 1) can get out with its data thru the uplinks on module 2, 5 or 6 (if I want), via the stacking cables...

 

Plenty of examples are mentioned in the VC Ethernet cookbook... Please check that one...

 

 

Kr,

Bart

--------------------------------------------------------------------------------
If my post was useful, clik on my KUDOS! "White Star" !
Bob_Vance
Esteemed Contributor

Re: is Virtual Connect stacking required?


>> VC-FC
Good catch, Bart!!
Of course.

So, the Domain mgt Meta traffic must be occurring on the OA mgt network.
The "two-domain" scenario is unnecessary and out.
Although, I'm not sure about MAC tables.
Again, there's just not enough Theory of Op info.


>> Without the stacking cables between 1 and 5
>> and another one between 2 and 6,
The last phrase is a little ambiguous.
So, just to be clear, you did mean by that:

"No stacking cables between 1,5
  and
  no stacking cables between 2,6.
"
I.e, no vertical stacking at all between the VCs within a single enclosure.
(I assume, "Yes", since that's what the thread is about ;>)

So, what caused you not to use vertical stacking in your environment?
Or did you only try it out for curiosity.


>> ... VC Ethernet cookbook
That is a fine document, but it does address the issue of vertical stacking within an enclosure at all.
All the examples have just two VCs in each enclosure.



tks
bv

"The lyf so short, the craft so long to lerne." - Chaucer
Bart_Heungens
Honored Contributor

Re: is Virtual Connect stacking required?

Hi,

 

All modules can communicate with each other through the signal midplane... However there is always communication via the OA...

 

2 VC domains in 1 enclosure is indeed not possible...

 

In my case Yes I have stacking cables between modules 1 and 5 and another one between 2 and 6... What I meant to explain is that, even without those cables, I can manage all modules... Via the OA and signal pidplane...

 

I know 1 scenario where the customers has all client and management trafic on modules 1 and 2, and only iSCSI trafic on modules 3 and 4 via the additional mezzanine card... Since it is a complete seperate type of trafic, stacking is not needed...

 

 

Kr,

Bart

--------------------------------------------------------------------------------
If my post was useful, clik on my KUDOS! "White Star" !
Bob_Vance
Esteemed Contributor

Re: is Virtual Connect stacking required?

Thanks, Bart.

The separate iSCSI which you mentioned is the exact scenario that I will be dealing with, so I'm going to try it.

We will be doing a Flex-10 upgrade for VC 1/10G Enet modules in bays1,2 and will have a downtime window to be able to play with it --
basically just disconnecting the current vertical CX4 stacking and see what happens.


>> All modules can communicate with each other through the signal midplane..

My understanding is this:

VCs only communicate *horizontally* via the midplane and lacking vertical stack cables, cannot communicate  vertically.

The VC 1/10G Enet has hidden X0 *always* connected horizontally across midplane.
VC-Flex10s use X7 & X8 horizontally, but if an SFP is installed in either or both ports, then the port(s) are disabled horizontally.

Do you disagree?



bv

"The lyf so short, the craft so long to lerne." - Chaucer
Bart_Heungens
Honored Contributor

Re: is Virtual Connect stacking required?

Hi,

 

Correct. In the older modules the X0 was hardwired through the midplane and could not be changed.

 

In the Flex modules the customer can choose for himself where he wants to make the interconnection. Inside or outside the enclosure.

 

Best practice is however using the internal connections so that the external switches are not (ab)used for trafic that can perfectly be handled inside...

 

There is indeed a difference in data paths and mgmt data paths ... VC itself for its config goes thru the OA, 'real' data goes directly via the signmal midplane to the servers...

 

Kr,

Bart

--------------------------------------------------------------------------------
If my post was useful, clik on my KUDOS! "White Star" !
Bob_Vance
Esteemed Contributor

Re: is Virtual Connect stacking required?

>> There is indeed a difference in data paths and mgmt data paths ... VC itself for its config goes thru the OA

 

This is the crucial idea and was the nub of my original query.

 

I'm going to leave this open until I have done my upgrade and will post results thereafter.

 

bv

"The lyf so short, the craft so long to lerne." - Chaucer
Psychonaut
Respected Contributor

Re: is Virtual Connect stacking required?

Bart, that is some great info - I was looking to white board this out a little today and take back some of what I had suggested earlier. But it looks like you guys have hashed it all out.
Bart_Heungens
Honored Contributor

Re: is Virtual Connect stacking required?

That's the reason why this forum exist... To share this kind of information.

 

Do not forget to assign kudo's, it is also appreciated... ;-)

--------------------------------------------------------------------------------
If my post was useful, clik on my KUDOS! "White Star" !
Brunot38
New Member

Re: is Virtual Connect stacking required?

Hello,

 

how did the tests go without vertical stacking ?

 

I have a similar setup ( that I am explaining in a  new post " HP Virtual Connect - Design with no vertical Stacking" )

 

I would really like to know if a setup withoug vertical stacking is working. It would be much appreciated as I am stuck on this..

 

Thanks

 

Brunot38