Boot resiliency ?

[AndyMcC]

Hi, (1st. post so be nice..)

 

I've not used DSM before, but it looked like an interesting option for a new home/small business NAS I need to build.

 

I just installed DSM 6.2.2/DS3615 onto a HP Microserver N54L, using Jun's loader 1.03b. The system has two disks currently in RAID1. I fitted an HP NC365T 4-port card prior to the installation. This was all quite straightforward.

 

However, I find that after installation, the installation USB drive must remain present, for the system to start up ?

 

This is no good at all, as a fundamental requirement for the system is that there should be no storage devices that are single points of failure.

 

I had assumed, that DSM would install each hard disk with a working boot environment, so the system could be started up in the event that any one disk failed. Is this not the case ?

 

If this is a design limitation with Xpenology, or if it can be fixed, I'd like to know ASAP...

 

Thanks.

 

 

Edited August 3, 2019 by AndyMcC

[NooL]

Hi Andy - Welcome, I am a new user as well.

 

Yes you are absolutely correct, the USB stick must remain present in your pc at all times for the system to boot.

 

But you are also correct that the system can still be started if a disk fails, as you say the Synology OS is installed on each drive in the system.

 

The whole reason for the USB key is that it's a LOADER for the Synology OS, it does just that, LOADS your system

 

Since you made your USB stick from a .IMG file, its easily re-creatable if your usb stick should catch fire or whatever You would just need to change the VID and PID in the grub.cfg file like you did first time around, make a new USB stick, stick it into your machine, boot and do what you normally do

 

I hope this makes sense

 

I'd also like to add that the system as a whole, is infact incredibly robust and resilient with your data, it will take pretty much everything you can do to it (Like messing with system files you shouldn't be after install) and at max, ask you if it should Restore/fix itself.

 

 

 

Edited August 3, 2019 by NooL
Addition

[bearcat]

@AndyMcC Hello and welcome to the "family"  just as @NooL stated, the USB stick must remain at all time (at least during boot)

as it's not an "installation USB", it is a bootloader allowing you to boot your system and install DSM on your HDD's using the .pat file

It might be seemd as a single point of (possible) failure, but as said you can easily create a new one of needed.

Even the original Synology boxes use a bootdevice to boot before handing over the system to the HDD's

(thats why you can buy a box with no HDD installed, and still be able to install DSM on your preferred disk's.).

 

What you can, and should do, is to make sure you take regulary backups of you configuration and keep it off-NAS.

 

btw:

Seeing you are using a NC365T with DSM 6.2.2, could you check what deviceid it presents to your DSM?

(How to: SSH to your working NAS, log in as admin, type in this command: lspci -k | grep 0200  )

 

Edited August 4, 2019 by bearcat

[AndyMcC]

Gottit guys, thanks.

 

It's a bit of a learning curve for me, not done much sysadmin stuff for a decade or so.. eg. I still think of USB as a dodgy 'consumer' thing.. lol.. I could always have two copies of the USB stick fitted, then if one dies it'd be a quick job to flip the BIOS to boot from the other one. I intend to do some DR testing with this rig before comitting it to a full production role with all my precious data on it. I still haven't figured out how I'll do backups..

 

My NC365T loads the 'igb' kernel module, Intel 82580 chip, and is device id PCI\VEN_8086&DEV150E.

[jensmander]

Hi & welcome.

 

Using two sticks is probably not a good idea. As mentioned before you can just keep a copy of your synoboot.img in a safe place. If anything happens to your current usb stick you can easily reflash a new one and adjust the vid&pid from the new stick, that’s all.

 

Afaik it never happened to any of my Xpenology boxes since DSM 5.x that a boot stick bricked. The stick is only accessed during the initial boot process after BIOS post phase. So there are only a few read operations on every single (re)boot process.

[Polanskiman]

As mentioned above, the USB key you are using is merely a loader. Once DSM is loaded that usb key is technically useless. You could unplug it and DSM would still work fine. Problem is, if for whatever reason the box reboots then DSM can't boot.

 

Xpenology is no different than a real Synology in that regard. A real Synology box has an internal USB type loader. XPEnology simply replicates that except the usb is external. Your N54L has an internal USB port so you could use that one if you don't want to have a USB visible.

 

One comment I wanted to make (and this was perhaps the most important one), if you intend to use this a production box, and more specifically for professional related tasks I would make sure to set up a proper backup system. Although DSM is vanilla and no modification is done to the OS, XPEnology loader is a hack and no one here can warranty that you will be worry free. In many years of using XPEnology I have never had any major issue specially after setting up my boxes but people do have issues sometimes (mostly due to carelessness though). I personally use XPEnology for leisure, not for professional tasks. For that I use real Synology boxes. I manage 3 for them, onsite and offsite.