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Re: Redundant midplane in a Blade System

 
Augusto amos
New Member

Redundant midplane in a Blade System

Anyone knows if a Blade System has a redundant midplane or backplane in a HP Blade System?
Have any document for this issue?

9 REPLIES 9
James ~ Happy Dude
Honored Contributor

Re: Redundant midplane in a Blade System

Hello Augusto,

"I" don't think this has been achieved (yet!!) by HP.

Regards,
James.
David Claypool
Honored Contributor

Re: Redundant midplane in a Blade System

There are no active components on the midplane (there is no backplane) to fail. The only possible failure is a mechanical failure. Half of all the connections are routed east (one side) and the other half are routed west (the opposite side). With teamed network/SAN connections and best practice of teaming across east/west, a mechanical failure will not take communications down.

Also, unlike our major competitor, we do not route power through the signal midplane--it is a separate plane--basically a solid copper bar for + and a solid copper bar for -.
reverie_1
New Member

Re: Redundant midplane in a Blade System

Hi, I would just like to add, yes, the HP BladeSystem doesn't have a redundant midplane. That is actually one of the biggest strike points IBM attacks HP with. But I've always told customers that in the 4 or so years the Blades (in general) have been in the market, there is practically less than 2% failure rate in terms of the midplane or the backplane. A reason why HP doesn't have a redundant midplane is because there aren't really any active parts or components in it. So the chances that it will ever break down are very remote and will most likely never happen.

The failure rate is really exaggerated, when the main focus should actually be in the active components that are really more prone to failure. These are the power supplies, the fans, the disks, all of which are more vital parts that will eventually be the causes of downtime of any blade solution. And time and time again, it has been proven that those are really the components that you need to look out for if your worry is blade downtime.
aboerup
Frequent Advisor

Re: Redundant midplane in a Blade System

As David above said, IBM's touting of a redundant midplane is not that big of a deal. In fact the way IBM does their 'redundant midplane' is actually worse (less reliable) than HP's midplane!

HP's midplane is really just a bunch of cables in the form of a PCB with connectors on it. How often do high quality cables go bad? Think about it.

IBM's midplane has tons of active components (things like processors capacitors etc) that heat up, cool down and might break and potentially take part of the enclosure down with it. What IBM touts as being 'redundant' about their midplane is that each blade system has 2 connectors to the midplane which they claim makes it redundant.
Sadly this is not the case as if you lose one connector to the midplane you could lose half of your connections to your I/O equipment or lose enough power to shut your server down!

In this particular instance (a midplane) more parts is not necessarily better!

Even aside from this whole marketing standpoint the C7000 really blows away any offerings by IBM if you ask me.
GruffMeister
New Member

Re: Redundant midplane in a Blade System

What is exactly is a midplane as opposed to a back plane - Excuse storage newbie!
Patrick Terlisten
Honored Contributor

Re: Redundant midplane in a Blade System

Hello,

the "silver bullet" of the non-redundant backplane is not a "silver bullet". IBMs backplane is active, those of HP is passive. Just some plastic with some connectors. :) I've heard that only <4% of the blade enclosures in the market (p- and c-Class) died with a defective back-plane. But I saw 2 of 16 IBM blade enclosures dying with a defective backplane within two years. Any questions? ;)

Best regards,
Patrick
Best regards,
Patrick
aboerup
Frequent Advisor

Re: Redundant midplane in a Blade System

Gruffmeister,
A midblade in a bladesystem is called such because there are things that plug into both the "front" side (blade servers, storage blades, tape blades, etc) and the "back" side (ethernet switches, fiber switches, management switches, infiniband switch, etc).
Since its more or less in the middle of the chassis they have taken to calling it a midplane.
Tavrez_1
Occasional Advisor

Re: Redundant midplane in a Blade System

I went for HP training and their midplane only fails if there is physical damage while forcing a blade in the bay or during a surge.Otherwise they shouldnt fail.

Re: Redundant midplane in a Blade System

Another case in wich the midplane can fail is:
- enclosure has some bays without blade and blanks and there is much dust in room
- when installation people remove the mid plane to decrease weight of enclosure and then they not properly reinsert it.

It's very important not to insert blades if midplane is not aligned. To check the alignment of the midplane is often useful to see if the 4 rear thumbscrews are all properly closed in a 90├В┬░ angle.

Remember: If the midplane is not correctly inserted extract blades 7cm before correcting its alignment.