What's the use of External HBA

[Fastline]

Hello,

I've used a few LSI based HBA cards and they have worked fine. However, they were all having internal ports. I also saw that a few LSI models have an external SAS Port. I've no idea what's the use of an external SAS Port and how to use that. Can anyone please explain?

Thanks

 

[Patrick M. Hausen]

There are disk shelves with SAS connectors.

 

[LarsR]

They are for jbods, external Disk shelves.

 

[Fastline]

There are disk shelves with SAS connectors.

I guessed it.

Like this one for example?

MB998SP-B_Rugged 8 x 2.5" SAS/SATA HDD/SSD Moblie Rack Enclosure for 5.25" Bay

global.icydock.com

 

[Patrick M. Hausen]

Not quite. This goes into a 5.25" mounting bay and is connected inside the PC.

More like this:

SC216BE1C-R609JBOD | 2U | Chassis | Products | Supermicro

216BE1C-R609JBOD

www.supermicro.com

 

[Fastline]

Not quite. This goes into a 5.25" mounting bay and is connected inside the PC.

More like this:

SC216BE1C-R609JBOD | 2U | Chassis | Products | Supermicro

216BE1C-R609JBOD

www.supermicro.com

Okay, so its like you have a server and that has a few SAS/SATA Drive which is connected via onboard SAS/SATA and you also use the Internal SAS/SATA ports from HBA Card and if you need more storage, put drives in another box and connect those via external HBA Card. Is that correct?

 

[Patrick M. Hausen]

Yes. Or you have a server with just a boot drive and half a dozen of these external shelves connected.

Enterprise storage frequently looks like this:

 

[Fastline]

Yes. Or you have a server with just a boot drive and half a dozen of these external shelves connected.

Enterprise storage frequently looks like this:
View attachment 72287

Cool. So, the shelves connects via Backplane and how does it connects via the main server? The main server would have the external HBA right?

 

[LarsR]

Both need hba's with external connectors.

 

[Patrick M. Hausen]

Yes, what else? SAS cable from HBA to shelf. Lots of HBAs if necessary ...

Like one of these:

 

[Patrick M. Hausen]

Both need hba's with external connectors.

Yes, but in case of the shelves these are practically always a fixed part of the product.

 

[Fastline]

Umm, my question is suppose i have disk shelves and a main server now i make connection from the server to the shelves using the external HBA?

Secondly, i also came to know about SFP based HBA Cards. How does that work?

 

[Patrick M. Hausen]

Umm, my question is suppose i have disk shelves and a main server now i make connection from the server to the shelves using the external HBA?

Yes.

 

[Arwen]

For SOHO use, something smaller than a full rack width of disks can be used;

RS6414S/6418S Overview | | HighPoint Technologies, Inc.

The HighPoint RocketStor 6414S/6418S external 4- and 8-bay 6Gb/s SAS/SATA storage tower enclosures are designed for use with RocketRAID hardware.

www.highpoint-tech.com

These don't have SAS Expanders, so need one SAS / SATA lane per drive.

I have no connection to that company or product, nor have any knowledge of how well it works.


As for SFP on a HBA, that sounds like Fibre Channel. Not something generally usable with TrueNAS.

 

[Fastline]

As for SFP on a HBA, that sounds like Fibre Channel. Not something generally usable with TrueNAS.

Oh, i see. But in general, how does that work?

 

[Patrick M. Hausen]

Oh, i see. But in general, how does that work?

Let Me Google That

For all those people that find it more convenient to bother you with their question than to google it for themselves.

letmegooglethat.com

 

[Fastline]

Let Me Google That

For all those people that find it more convenient to bother you with their question than to google it for themselves.

letmegooglethat.com

Ouch. It's general that everyone knows Google is out there. But sometimes some people wants to know in a more simplified way which can be understood easily ;)

So, how does the SFP HBA work?

 

[Patrick M. Hausen]

What do you expect? Me retyping the Wikipedia article? Fibre Channel works like this:

Fibre Channel - Wikipedia

en.wikipedia.org

 

[Fastline]

What do you expect? Me retyping the Wikipedia article? Fibre Channel works like this:

Fibre Channel - Wikipedia

en.wikipedia.org

Nope. I'll dig the internet. Thanks

 

[Arwen]

Fibre Channel is a complex subject, and generally SOHO users don't need to use or know about it.

Fibre Channel is a full blown, extreme speed, (up to 64Gbit/ps, per channel), multi-path, multi-initiator storage networking protocol.

Trying to describe it in a paragraph means actual research to get the words right for those of us that know about FC, but not work on it regularly. So, that sentence is what I can say... but still had to look up the current top speed, (which is debatable).