Boot from SSD - still have doubts - size and mirroring

[AndroGen]

The build comes to the "final" assembly stage, and I am still puzzled in regards to the boot device.

First, what I have understood from other discussions and posts, and would appreciate you validation, whether it has been understood correctly:

• Boot device can be very small - even 16GB might be sufficient. Some posts refer to 120-250GB SSD, but no posts with 500+GB SSDs
• Logging system resigns on the same drive in /var/log folder, the logging system overrides the logs on regular basis - no high requirements, unless some copying / log preservation mechanisms are activated
• It is recommended to have boot device to be mirrored (redundancy), but this is rather a nice to have for an ordinary system
• Having anything else (e.g. cache) on the boot device is not recommended, as this is not supported by FreeNAS, and will increase the risk of failure during the update/upgrade
• After the boot no high load on the Boot device as most of the stuff is in the memory - hence the SSD speed is not really critical, no need to go for NVMe M.2 devices

Question

Increasing the size of the log files, and the duration they are kept in the system - this would be the only reason to have bigger BOOT drive, otherwise it would be a waste of space.

Do I miss anything?

Any feedback / correction would be appreciated

 

[microserf]

ZFS will detect an error on a boot device but requires a mirror to correct it. Whatever you do, backup your configuration religiously. FreeNAS does not store the OS in memory but can keep reporting data in a RAM disk if you like.

Log files can be stored in the system dataset - it may be the default these days, I'm not sure. The system dataset is located on one of your storage pools and can be moved.

https://www.ixsystems.com/documentation/freenas/11.2-U4.1/system.html#system-dataset

 

[Stevie_1der]

Boot device can be very small - even 16GB might be sufficient. Some posts refer to 120-250GB SSD, but no posts with 500+GB SSDs

Yes, 16GB will be sufficient.
But it's hard today to get SSDs smaller than 120GB, except 16GB Optane M.2 NVMe for 25€ (although its potential would be wasted, but you wouldn't waste so much space).
For sure, you can get some crappy el-cheapo small SSD, but I wouldn't trust those.
And decent 120GB SSDs start around 20€, Kingston A400 was mentioned here some times.
Using a 500GB performance SSD as boot device ist just pure overkill, that's why nobody uses them.

It is recommended to have boot device to be mirrored (redundancy), but this is rather a nice to have for an ordinary system

It is highly recommended if you use USB thumb drives, as these are quite likely to fail.
If you use an SSD for boot, you don't need mirroring (at least for home use), because SSDs are far more reliable, and support SMART to check their health (this is impossible for USB sticks).
Nevertheless you should backup your configuration after changes, just in case...

Having anything else (e.g. cache) on the boot device is not recommended, as this is not supported by FreeNAS, and will increase the risk of failure during the update/upgrade

Exactly.
But maybe this changes sometimes, SSDs are now recommended, so it could be the developers might think of permitting to put more stuff on the boot device.
Write cache will never be a good idea to have on the boot device, because it requires high performance drives.
L2ARC might work in theory, but as long as it's not officially supported, don't do it.

After the boot no high load on the Boot device as most of the stuff is in the memory - hence the SSD speed is not really critical, no need to go for NVMe M.2 devices

Exactly.
The only exception would be if you are using all SATA connections, and you cannot add a HBA, or don't want to add a HBA.

 

[AndroGen]

Thanks @Stevie_1der, your reply is very much appreciated.

Than it's more or less settled topic.
BOOT is going to be: Single 250 GB SDD drive (there is no big price difference to 120)

 

[rvassar]

I boot on a mirrored pair of Patriot Memory "Flare" 60Gb SSD's that I picked up on clearance for $18 each. It looks like they're no longer in production. My suggestion is use the smallest cheapest SSD you can find.

 

[Snow]

I used the Kingston off of Amazon its like $30. Ever since I switched over to ssd's I have not had a problem with a boot drive.
Freenas eat these usb's I have more just could not find all of them for the pic. A400 SSD Link to ammazon

 

[Tigersharke]

I used the Kingston off of Amazon its like $30. Ever since I switched over to ssd's I have not had a problem with a boot drive.
Freenas eat these usb's I have more just could not find all of them for the pic. A400 SSD Link to ammazon
View attachment 30833

Some USB sticks fail more quickly than others, just the nature of FreeNAS and the intended purpose of the stick (non-continuous use). The all-metal Kingston in the photo lasted longer for me than some plastic encased ones labelled "BestRunner" which got warm and failed, every one of those I tried met the same fate. If nothing else, those usb sticks we may have used for FreeNAS boot devices have been tested to failure, those that survived longest would be best choices for sneakernet use or other non-constant use (as intended). I've also run into some strange issues with other usb sticks (which I no longer possess) which sometimes needed a quirk applied simply to mount them. It is obvious that there is a lot less quality control and adherence to standards with usb sticks. It is scary to think that some people use these simple usb sticks as their entire backup solution, not just as an eventual failed boot device.

 

[Snow]

Some USB sticks fail more quickly than others, just the nature of FreeNAS and the intended purpose of the stick (non-continuous use). The all-metal Kingston in the photo lasted longer for me than some plastic encased ones labelled "BestRunner" which got warm and failed, every one of those I tried met the same fate. If nothing else, those usb sticks we may have used for FreeNAS boot devices have been tested to failure, those that survived longest would be best choices for sneakernet use or other non-constant use (as intended). I've also run into some strange issues with other usb sticks (which I no longer possess) which sometimes needed a quirk applied simply to mount them. It is obvious that there is a lot less quality control and adherence to standards with usb sticks. It is scary to think that some people use these simple usb sticks as their entire backup solution, not just as an eventual failed boot device.

I've had best luck with Scan disk Usbs off of Newegg, the ones I get off amzon seem to fail not sure if they are fake or what but it seems amazon has been dealing with counterfeit stuff for awhile now or it could be a bottom of the barrel thing. It is why I will only buy from sellers of the brands off of amazon and stay away from 3rd party.

 

[AndroGen]

Some USB sticks fail more quickly than others....
It is scary to think that some people use these simple usb sticks as their entire backup solution, not just as an eventual failed boot device.

I had few USB failing miserably, likely never trusted them as a long term solution - hence keeping freeNAS on USB was not considered as a viable option.
I like to set-up the system and then used as long as possible, preferably with minimum extra work.
There is still one Atom based custom built server for no longer existing on the market Logitech Squeezebox devices - works fine, goes up by itself, goes to sleep when no music listened - no maintenance for 10+ years (it's off the main network, with no internet connection).