Bad JBOD Controller Experience

[Chris Moore]

Video, that link looks like a FreeNAS user guide?

Sorry, I don't know how I put the wrong link in.
This is what I was trying to link to:
https://www.youtube.com/watch?v=R3f-Sr6y-c4

 

[nightshade00013]

So this blew my mind. I will definitely be adding an L2ARC drive as soon as I have the $$ to drop on a 1 Tb SSD. Good stuff.

Just remember that the best practice is to MAX the ram before you add L2ARC or at least get as close to it as possible. A system that only supports 32GB of RAM is also a poor candidate for that much L2ARC since the L2ARC uses RAM for the index so you lose system memory for a slower but expanded ARC. https://forums.freenas.org/index.php?threads/formula-for-size-of-l2arc-needed.17947/#post-97362 And even then it is not ideal. https://forums.freenas.org/index.php?threads/formula-for-size-of-l2arc-needed.17947/#post-112590

You can throw money at the problem with super sized drives and such but if you are going to do that you may as well set aside for a different board than what you posted earlier and get a TON of ECC ram. A dual CPU X9 series board would be the cheapest way to do it with a pair of cpu's and 8GB sticks of DDR3 ECC ram to fill every slot you will be farther ahead than a system with 32GB of RAM and a HUGE L2ARC. If you can afford the RAM a DDR4 system would be good as well but the the cost of the memory is so high you really need to have a good use case for it. And ultimately since you went with an i5 and non ecc ram you are taking a larger risk with your data already and the more complex you make the system the higher the risk.

 

[Adam Tyler]

Good information.. Ya, I think I am at my limit and this is still going to be a HUGE upgrade from my old school 6 drive ZFS system built on AMD Opteron platform. I think I may opt to do read caching at the VMware host level instead. Flash Cache from them is a "write through", but read cache that can be enabled per VM. I only have 16 Gb RAM today for this system and will eventually upgrade to 32 depending.

 

[Adam Tyler]

So in order to install FreeNAS on mirrored hard drives, would you simply select both drives at install here? For example in this screenshot you would select both 20 Gb drives?

 

[Chris Moore]

So in order to install FreeNAS on mirrored hard drives, would you simply select both drives at install here? For example in this screenshot you would select both 20 Gb drives?

Absolutely. Highlight the drive, press space to select, highlight the next drive, press space to select, then press enter to continue to the next screen.

Edit, you can actually select as many drives as you want to install onto. I did a 3 way mirror one time.

 

[Adam Tyler]

Sweet. It builds a little zfs pool and vdev just for the OS or is it using a different technology for the mirror?

 

[Adam Tyler]

Here is a post with a nice 'step by step' of the process of adding a SLOG to an existing pool:

https://forums.freenas.org/index.ph...n-ixsystems-hardware.46032/page-3#post-313538

Any special instructions for adding a "mirrored" slog or would this post cover it?

 

[Chris Moore]

Sweet. It builds a little zfs pool and vdev just for the OS or is it using a different technology for the mirror?

No, nothing special, it just creates a ZFS pool, named 'freenas-boot' for the system to boot from.

 

[Adam Tyler]

No, nothing special, it just creates a ZFS pool, named 'freenas-boot' for the system to boot from.

Thanks, and nothing gets constantly written to it right? It only gets written to when config changes are made? Using some "iffy" SSDs for the boot volume. Never used Patriot before. Usually stick with Samsung, but these were really really cheap.

 

[Chris Moore]

Any special instructions for adding a "mirrored" slog or would this post cover it?

Sadly, there doesn't appear to be away to do a mirrored slog from the GUI.

The command to type at the command prompt is this:

zpool add pool-name log mirror device-name device-name

The thing I would do is follow the instructions I gave to add one, then remove it, then add the other one and remove it. This will have formatted them and given them GPT names. Then when you add the mirror from the command prompt, you can reference the drives by their GPT name.

 

[Chris Moore]

Thanks, and nothing gets constantly written to it right? It only gets written to when config changes are made? Using some "iffy" SSDs for the boot volume. Never used Patriot before. Usually stick with Samsung, but these were really really cheap.

There is a little activity but it isn't a lot unless you have your system dataset moved to the boot-pool.

 

[Adam Tyler]

Sadly, there doesn't appear to be away to do a mirrored slog from the GUI.

The command to type at the command prompt is this:

zpool add pool-name log mirror device-name device-name

The thing I would do is follow the instructions I gave to add one, then remove it, then add the other one and remove it. This will have formatted them and given them GPT names. Then when you add the mirror from the command prompt, you can reference the drives by their GPT name.

Not a big deal.. I'm somewhat comfortable in an SSH session running commands against the ZFS pool. Had to do it quite a bit with NAS4Free. Thanks for showing this to me. I would have been scratching my head. Any way to monitor or confirm once it is in place? Like if I want to list the zpool status, would it show up as a "special" vdev? Easy way to monitor write performance to the zil/SLOG? Will be fun to remove and add and compare speed.

 

[Adam Tyler]

There is a little activity but it isn't a lot unless you have your system dataset moved to the boot-pool.

The system dataset not being located on the boot-pool by default I assume? I'm not familiar with the term "system dataset". Does this refer to the primary storage zpool or something else?

Sorry I have so many questions. Think I am just about there though. Luckily the iSCSI and networking config I have pretty much down. Most of my confusion surrounds the ZFS config side of things.

 

[danb35]

The system dataset not being located on the boot-pool by default I assume?

The .system dataset is stored on the boot pool until a data pool is created. At that time, by default, it's moved to the first data pool that's created.

I'm not familiar with the term "system dataset".

http://doc.freenas.org/11/system.html#system-dataset

 

[Stux]

How awful is a Samsung 128 Gb EVO SSD drive to use for something like this? Bad idea?

It’s certainly not ideal.

Ideally you want a drive with Power Loss Protection (PLP)

And the Evo, since it lacks PLP, will have slow Sync Writes too.

 

[nightshade00013]

https://www.servethehome.com/buyers...as-servers/top-picks-freenas-zil-slog-drives/
good reading for SLOG/ZIL

 

[Adam Tyler]

So if you are mirroring your boot drives for FreeNAS, what drive gets configured in BIOS as the first boot device? Should each of your mirrored drives be set as first and second boot device or....?

 

[Adam Tyler]

I'm not gonna lie, getting a tad frustrated.. Trying to upgrade the firmware on this 9207-8i controller and getting this "failed to initialize pal". Booting to FreeDOS and running sas2flsh.exe -f 9207-8.bin.. From what I can find online it means I need to flash using a different board with UEFI support?

 

[danb35]

From what I can find online it means I need to flash using a different board with UEFI support

Or just do it from inside FreeNAS, which includes the sas2flash utility.

 

[Adam Tyler]

Or just do it from inside FreeNAS, which includes the sas2flash utility.

Alrighty. I will go ahead and just install the OS first then....