FreeNas Build Components

[jchan94]

Hi all, 

 

Looking to get my FreeNAS build underway. Here are the components that I'm looking to use for this build. Please let me know what you think.

 

Goals

1. iSCSI Targetting for VMWare
2. Plex Media Server
3. Raidz2 for redundancy of my photos, documents, etc

Questions

1. Do I need a raid card for iSCSI targetting with FreeNAS?
2. Do I have any bottlenecks in my system?

 

Motherboard

SUPERMICRO MBD-A1SRi-2758F-O

http://www.newegg.com/Product/Product.aspx?Item=N82E16813182855

 

Ram

16GB ECC RAM 

http://www.newegg.com/Product/Product.aspx?Item=N82E16820239958

 

Drives

5 x 4TB; Raidz2 = 12TB 

WD Red Drives

 

PSU

Rosewill 500W Gold 

http://www.newegg.com/Product/Product.aspx?Item=N82E16817182329&cm_re=500w_gold-_-17-182-329-_-Product

 

Case

Still deciding what to put it in.... PSU will change if I find a small case at good price.

 

 

 

[Vitalius]

wpirobotbuilder alpenwasser

I know nothing about what's required for iSCSI. 

jchan94 You shouldn't have a major bottleneck in your system AFAICT. I have that motherboard and it performs very well. The RAM is compatible with it as I also have that RAM. 

Your biggest bottleneck is probably going to just be your I/O. Read/Write speeds on the drives themselves, basically.

That PSU will not work. The Avoton CPU makes use of Intel's C6 & C7 low power states. The PSU has to support those to be able to do it, otherwise it will just shut the system off when the CPU tries to enter that state. 

Here is a list of PSUs that support those states. It's fairly old (2013), and I don't know if new PSUs have been updated to support them all, but I doubt it. 

This is the PSU in my system. I stuck the computer in this case. I like them. Others don't. To each their own. Though they are high quality.

[Atomicnerd64]

Hi all, 

 

Looking to get my FreeNAS build underway. Here are the components that I'm looking to use for this build. Please let me know what you think.

 

Goals

1. iSCSI Targetting for VMWare
2. Plex Media Server
3. Raidz2 for redundancy of my photos, documents, etc

Questions

1. Do I need a raid card for iSCSI targetting with FreeNAS?
2. Do I have any bottlenecks in my system?

 

Motherboard

SUPERMICRO MBD-A1SRi-2758F-O

http://www.newegg.com/Product/Product.aspx?Item=N82E16813182855

 

Ram

16GB ECC RAM 

http://www.newegg.com/Product/Product.aspx?Item=N82E16820239958

 

Drives

5 x 4TB; Raidz2 = 12TB 

WD Red Drives

 

PSU

Rosewill 500W Gold 

http://www.newegg.com/Product/Product.aspx?Item=N82E16817182329&cm_re=500w_gold-_-17-182-329-_-Product

 

Case

Still deciding what to put it in.... PSU will change if I find a small case at good price.

I have no experience with iSCSI so I'll skip that part. case I'd say go with the Silverstone one that linus used in the insane compact nas 2014 video. also...freenas' minimum recommendation is 16GB or ram but if you want to use better features like the one that if you have the same file in two locations it will store one copy of it but it will show up in both locations I'd recommend 32 gigs and to answer the "does it really need it?" yes, freenas is a memory hog. I have tested it on multiple machines and I think that for raid Z2 you would benefit from more ram since you have the hardware that can take advantage of more advanced things. your system's only bottleneck is the cpu but since you can't change it might as well not think about it. if you are looking for a better mobo with an embedded, passively cooled cpu there is the acrock c2750d4i with an 8core cpu and 4 full sized ddr3 dimm slots. hope this helped

[jchan94]

wpirobotbuilder alpenwasser

I know nothing about what's required for iSCSI. 

jchan94 You shouldn't have a major bottleneck in your system AFAICT. I have that motherboard and it performs very well. The RAM is compatible with it as I also have that RAM. 

Your biggest bottleneck is probably going to just be your I/O. Read/Write speeds on the drives themselves, basically.

That PSU will not work. The Avoton CPU makes use of Intel's C6 & C7 low power states. The PSU has to support those to be able to do it, otherwise it will just shut the system off when the CPU tries to enter that state. 

Here is a list of PSUs that support those states. It's fairly old (2013), and I don't know if new PSUs have been updated to support them all, but I doubt it. 

This is the PSU in my system. I stuck the computer in this case. I like them. Others don't. To each their own. Though they are high quality.

 

Thanks for the information. I really appreciate it.

 

I'll look at another PSU. 

[Vitalius]

if you are looking for a better mobo with an embedded, passively cooled cpu there is the acrock c2750d4i with an 8core cpu and 4 full sized ddr3 dimm slots.

"A better mobo". Supermicro makes top notch motherboards imho. ASRock's server motherboards have been considered highly as well. I don't think he can go wrong with either. 

Same CPU inside both, of course. Both are also passively cooled. It's basically a choice between 4 Ethernet Ports & 12 SATA ports.

[Atomicnerd64]

"A better mobo". Supermicro makes top notch motherboards imho. ASRock's server motherboards have been considered highly as well. I don't think he can go wrong with either. 

Same CPU inside both, of course. Both are also passively cooled. It's basically a choice between 4 Ethernet Ports & 12 SATA ports.

my bad, I checked the motherboard out but I didn't see the actual cpu model. in that case his motherboard choice is what I'd go with. again it was my fault for not looking enough into it.

[wpirobotbuilder]

Goals

1. iSCSI Targetting for VMWare
2. Plex Media Server
3. Raidz2 for redundancy of my photos, documents, etc

Questions

1. Do I need a raid card for iSCSI targetting with FreeNAS?
2. Do I have any bottlenecks in my system?

1)

 

You do not need a RAID card, iSCSI is done over the network, so any interface that carries an ethernet signal will be fine (your onboard networking will be fine). The only hardware upgrade that would help with iSCSI is a small SSD to be used a a synchronous log (ZIL), a 32GB SSD would be fine. This will help with VM performance, because iSCSI in FreeNAS writes synchronously to non-volatile storage to maintain disk consistency, and writing to a small SSD before committing to the disk is much faster than writing directly to the hard disks.

 

There are iSCSI HBAs and specialized cards with offloading, but they don't offer much in the way of performance gains, and just cause problems -- see this. Just get a tiny SSD and be happy. Also, get another 32GB SSD for your boot device, because you won't ever have to think about replacing your boot device (like you do with USB flash drives).

 

2)

 

No bottlenecks, but your CPU is probably more than necessary. You could get the 4-core version and save 50 bucks, and probably won't notice a difference.

[jchan94]

1)

 

You do not need a RAID card, iSCSI is done over the network, so any interface that carries an ethernet signal will be fine (your onboard networking will be fine). The only hardware upgrade that would help with iSCSI is a small SSD to be used a a synchronous log (ZIL), a 32GB SSD would be fine. This will help with VM performance, because iSCSI in FreeNAS writes synchronously to non-volatile storage to maintain disk consistency, and writing to a small SSD before committing to the disk is much faster than writing directly to the hard disks.

 

There are iSCSI HBAs and specialized cards with offloading, but they don't offer much in the way of performance gains, and just cause problems -- see this. Just get a tiny SSD and be happy. Also, get another 32GB SSD for your boot device, because you won't ever have to think about replacing your boot device (like you do with USB flash drives).

 

2)

 

No bottlenecks, but your CPU is probably more than necessary. You could get the 4-core version and save 50 bucks, and probably won't notice a difference.

 

Thank you for the insight on iSCSI. this is exactly the information that I needed. Just to confirm what you're saying about the SSD... it will essentially be working as a cache correct? 

[Vitalius]

Thank you for the insight on iSCSI. this is exactly the information that I needed. Just to confirm what you're saying about the SSD... it will essentially be working as a cache correct? 

ZIL stands for ZFS Intent Log. It's basically a log of what all ZFS needs to do in case something happens to the server before it can complete it's current set of writes. 

So... no. ZIL isn't a cache. It's a log of what do to with the cache (which is in the ARC which is in the RAM). 

I don't know how it interacts with iSCSI, but since I know iSCSI is file access over network, I imagine it has something to do with preventing corruption or loss of data when a network disconnect occurs (or any other bad things like it).

The ARC is always ZFS's primary cache which is stored in the RAM. You can set an L2ARC (Level 2 ARC) with an SSD, but there are very few situations where that's actually useful (mostly involving massive databases with high reads).

A blog about ZIL.

Here is the ZFS tuning guide.

And here is jgreco's guide to ZIL & SLOG.

He is very knowledgeable about FreeNAS & ZFS. He mentions iSCSI in there as it has asynchronous writes (which is relevant to an SLOG/ZIL).

Enjoy reading. If you feel the first too links are too technical, I recommend reading at least the 3rd one just so you understand how ZFS works and what things are (if you haven't and don't already, which based on your question, I assume you don't).

[wpirobotbuilder]

Thank you for the insight on iSCSI. this is exactly the information that I needed. Just to confirm what you're saying about the SSD... it will essentially be working as a cache correct? 

 

So... no. ZIL isn't a cache. It's a log of what do to with the cache (which is in the ARC which is in the RAM). 

I don't know how it interacts with iSCSI, but since I know iSCSI is file access over network, I imagine it has something to do with preventing corruption or loss of data when a network disconnect occurs (or any other bad things like it).

Basically, NFS and iSCSI require confirmation that a change to data on the FreeNAS server has been committed to non-volatile storage. This is useful because iSCSI targets are essentially hard disks -- you don't want the OS to write something to disk, then not have the disk tell you that it made it, or bad things might happen if there is a power fluctuation. NFS has a similar feature, but I don't believe CIFS has that feature.

 

You can turn off synchronous writes, but then you could risk data loss. There already exists a SLOG device for your pool, but it lives on your pool of drives. If they're all SSDs, there won't be any slowdown, but your disks are all mechanical, so writing synchronously will be slow because the slog is accessed in a very slow way. If you put the SLOG on an SSD, then it will be much faster to commit writes to disk.

 

All the ZIL (or dedicated SLOG device) does is move the SLOG from the pool of hard disks to a faster, non-volatile storage medium.