Connected Remote iSCSI LUNs Unavailable for Use

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DarfNader
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Connected Remote iSCSI LUNs Unavailable for Use

Post by DarfNader »

I realize this may not be the best channel for this as it seems to all be questions would appear to be about serving LUNs via iSCSI. This question is about mounting remote iSCSI LUNs to create Virtual Disks. I hope that's okay.

Anyway, my problem is after creating Virtual Disks which are mapped to a healthy LUN (iSCSI target is served by a Synology NAS), I do not see those Virtual Disks available for use to use for creating a shared folder as described in the QNAP user manual: [url]https://docs.qna ... l_disk.htm. The documentation advises that when creating a Shared Folder using Control Panel -> Privileges -> Shared Folders -> Create I should see the Virtual Disks appear along with the local Volumes which I do not.
2019-03-24 - QNAP, Create Shared Profile.png
I've also hunted around to see if these Virtual Disks appear anywhere else for use, but it's as if QNAP doesn't acknowledged their presence anywhere except for within Storage Manager -> iSCSI - > Remote Disks where Virtual Disks show as "Ready" and ext4 formatted.
2019-03-24 - QNAP, Remote Disks.png
While the LUNs were formatted ext4 on the Synology NAS, I formatted them again when mapping them for good measure. Is there some additional step that I need to perform to make these available for use for other QNAP storage apps like making a Shared Folder. I should note that the reason for this setup is that I wanted to get the best performance for external storage to create additional shared folders, snapshot volumes, and other backups so that I could have all storage with QNAP as the gatekeeper.

My setup is a QNAP TVS-473 with two pairs of bonded NICs each using balance-alb. One pair is coupled with the primary virtual switch and connected to my LAN while the other pair is coupled with virtual switch that I have designated for storage traffic and physically connected to an isolated switch that is not shared with other LAN traffic. Similarly my Synoptec DS-1813+ has a nearly identical network setup with two bonded NICs on the storage network where it is serving two 10 TB LUNs and no other file service traffic. The LUNs are both thin volumes with CHAP authentication that I have dedicated to be used by the QNAP 1-to-1 only and inaccessible for NFS file sharing, etc... Again, I am able to get QNAP Storage Manager to connect to the Synology-served LUNs by way of its IP address, iSCSI target, and CHAP authentication and can map each LUN to a Virtual Disk. As far as Storage Manager is concerned, the Virtual Disks are healthy. They simply do not appear available for use anywhere.

Any help on how to resolve this of suggest a workaround that offers the same level of performance with the same or better features, please let me know. Thanks!
2019-03-24 - QNAP, Disk Profile.png
2019-03-24 - QNAP, Storage Profile.png
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Re: Connected Remote iSCSI LUNs Unavailable for Use

Post by storageman »

When it works you should see them in Shared Folders against the volume names and File Station.
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Re: Connected Remote iSCSI LUNs Unavailable for Use

Post by DarfNader »

storageman wrote: Mon Mar 25, 2019 5:01 pm When it works you should see them in Shared Folders against the volume names and File Station.
Yes, that is what the documentation led me to believe as well, but as you can see from the screen clips in my OP, the only volumes that are available when creating a new Shared Folder are the local QNAP volumes. The remote iSCSI LUNs (Virtual Disks) do not appear in the drop-down list at all.

I guess what you're saying is that this is what I should be seeing and if I am not I probably should take it up with QNAP support.
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Re: Connected Remote iSCSI LUNs Unavailable for Use

Post by storageman »

No, that's not what I'm saying
I see two remote LUNs VLUN00 and VLUN01 off the Synology target.
Your Qnap based volumes have different names.
Did you check Shared Folders/File Station?

I think you need to look again.
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Re: Connected Remote iSCSI LUNs Unavailable for Use

Post by DarfNader »

Sorry for the slow reply. I kind of gave up.

I did in fact see the volumes in File Browser but I unless I am mistaken, I don't think that it will suit my needs which would allow me to use the synology space to replicate snapshots. I realize this may simply not be possible.

On the other hand, I suppose I could just as easily use this space for backups. I just hate Hybrid Backup Manager because it doesn't seem to support delta backups- just streaming- which really aren't proper backups. Is there a better tool out there for making standard backups of qnap folders/volumes that you like?
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Re: Connected Remote iSCSI LUNs Unavailable for Use

Post by DarfNader »

To repeat, while I can mount an iSCSI LUN from a remote Target and then see it in File Browser, I can't do much more with it. For instance, I can't find a way to use any QNAP tools to backup anything to that volume, whether its using Hybrid Sync, Snapshot Replication, or any of the QNAP specific iSCSI technologies of course. I am really not all that sure what I can use it for other than just having mounted storage. I can even use mounted USB drives to do this, but no, no iSCSI from another NAS. Why is this?
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Re: Connected Remote iSCSI LUNs Unavailable for Use

Post by storageman »

DarfNader wrote: Fri Sep 27, 2019 5:24 pm To repeat, while I can mount an iSCSI LUN from a remote Target and then see it in File Browser, I can't do much more with it. For instance, I can't find a way to use any QNAP tools to backup anything to that volume, whether its using Hybrid Sync, Snapshot Replication, or any of the QNAP specific iSCSI technologies of course. I am really not all that sure what I can use it for other than just having mounted storage. I can even use mounted USB drives to do this, but no, no iSCSI from another NAS. Why is this?
So use shares, no one is forcing you to use ISCSI.

ISCSI is for 3rd party software that doesn't like network shares or for virtualization.
Block storage feature in NAS is never intended for the NAS to see the internal file system.
The idea is the host can format the file system anyway it likes.

FYI Snapshot replication is available for LUNs.
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Re: Connected Remote iSCSI LUNs Unavailable for Use

Post by DarfNader »

I wanted to use iSCSI mainly out of speed and because I have a separate network (and switch) for the traffic. I have done enough research to see that QNAP really doesn't play nice with iSCSI LUNs that are not from another QNAP whether the server Synology NAS allocated the LUN as thick-provisioned, btrfs LUN and think-provisioned btfrs and EXT4 LUN but QNAP doesn't seem to care either way when it formats it. Also, can only see the mounted iSCSI LUN in the File Browser and no other QNAP apps seem to be able to use it at all including the Snapshot Manager so I am not sure how one would would be able replicate the snapshots to non-QNAP iSCSI LUN.

In any case, since I am not using separate virtualization hardware like ESX, iSCSI does not seem be something that have any value anyway. Furthermore, from what I read, my assumptions that dedicated iSCSI would be faster than an NFS or SMB share is likely unfounded. Therefore, if I have the hardware and NICs to do it, I might be better off having a dedicated network (the one formerly used for iSCSI) and just use that for network storage.

I have no idea if QNAP will make use of mounted SMB or NFS shares any better than iSCSI LUNs. I certainly hope say because the mounted iSCSI LUNs are basically useless. I would really like to replicate the snapsnots, not to mention make scheduled backups, onto a separate device- not use a stack of USB drives which I am using now which that, aside from being unreliable, an ugly stack of mismatched hardware, prone to failure, and surely a waste of electricity, are surely not the most efficient way to run backups. However, QNAP does allow me to use them as backup targets so hopefully they are not the only backup targets I can use!
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Re: Connected Remote iSCSI LUNs Unavailable for Use

Post by dannyfixit »

this is another very frustrating aspect of using QNAP NAS.
I kept seeing them show the iSCSI functionality in many previous releases and promotional ads. Being unfamiliar with the technology, I did my research into its history and benefits within a systems network in general. My conclusion was that this was a technology that could fill a need I had between my servers, including the QNAP. After configuring other servers to be Targets, adding disk drives to them and looking at security, it now looks like it doesn't work with QNAP apps, particularly the much touted HB3. WHY!?
The iSCSI volumes/LUNS connect to the QNAP initiator and show up in the iSCSI app as well as the File Manager app, but thats it. Can't use it for anything else. The technology makes it appear as a LOCAL SCSI drive, so why is it not available for use?
So much wasted time and effort to implement only to find it has not been implemented well by QNAP. They spend a ton of effort in HB3 allowing you to connect to every conceivable CLOUD in the whole atmosphere, but not to a local drive.
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Re: Connected Remote iSCSI LUNs Unavailable for Use

Post by DarfNader »

dannyfixit wrote: Fri Oct 04, 2019 11:03 pm The technology makes it appear as a LOCAL SCSI drive, so why is it not available for use?
So much wasted time and effort to implement only to find it has not been implemented well by QNAP. They spend a ton of effort in HB3 allowing you to connect to every conceivable CLOUD in the whole atmosphere, but not to a local drive.
You basically hit the nail on the head. It’s absurd. What’s worse is the same (mostly) applies to NFS/CIFS mounts too! Sure, you can set up rsync in HBU, but that is not a real backup strategy. What you want is to use HBU with versioned backup, but you can only backup to local disk, USB connected drives, or another QNAP. It’s a joke. Had I the choice I’d never buy another QNAP again. I bought it as a Plex server, a task this $1200 device is not up to, the NAS software is meh, and the restrictions are absurd. It really does make me ask “why even bother”? Synology NAS has MUCH better software if you want an off the shelf SOHO NAS or media vault, but if you want a powerhouse NAS / Media Player, buy a mini console PC that supports an i7 hexacore and a SCSI card which you can attach a RAID case and pack it full of disks. You can also get a nice M2 ssd capable PCIe cards if you need caching (though some boards do it on board) but lots of papers have shown storage tiering is far too expensive to do reliably (RAID1 on on SSD is very expensive and if you don’t, data loss is inevitable) vs the performance boost you get. Caching with LVM on the other hand with one SSD is easy!

And yes, you can backup your NAS to a remote share rather than make an ugly stack of USB enclosures for backups with is... just... awful...
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Re: Connected Remote iSCSI LUNs Unavailable for Use

Post by storageman »

Given the tone I'm not going to bother correcting a lot of inaccuracies and misinformation posted here.
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Re: Connected Remote iSCSI LUNs Unavailable for Use

Post by DarfNader »

storageman wrote: Fri Sep 27, 2019 11:53 pm So use shares, no one is forcing you to use ISCSI.

ISCSI is for 3rd party software that doesn't like network shares or for virtualization.
Block storage feature in NAS is never intended for the NAS to see the internal file system.
The idea is the host can format the file system anyway it likes.

FYI Snapshot replication is available for LUNs.
To take this back a few steps, I think that my frustration actually started here, probably because the reason I created the iSCSI LUN was to make a raw device which I hoped that QNAPa tool to connect to third-party iSCSI targets and mount LUNs would function in the same general manner than any iSCSI client host would use that storage in the manner you describe. However, this does not appear to be the case and I don't actually know what this function is for, frankly.

That said, I've long abandoned the idea of using LUN storage from a remote iSCSI target and simply tried to make use of file shares as you suggested. However, it became evident that HBS 3 still requires an RTRR server (a service that as far as I can tell is proprietary to QNAP) in order to perform backups to any storage outside of the NAS. Many other posters were quick to point out that I could schedule rsync jobs, but syncing is not the same as making backups. The principle differences I was concerned with was that backups have qualities that make them reliable for restores, such as point-in-time versions, and delta vs complete backup jobs. Sync jobs only move files from one place to another according to a schedule (or as the name suggests, synchronizes two locations with some scheme to manage collisions) but since this does not provide any means to recover your NAS from a corruption or data loss event that happens at some point before the last sync job. In any case, what made me the most frustrated about HBS 3 is that it purports to offer a 3-2-1 backup solution "simply" when in fact this can only be provided by using another QNAP NAS or a paid cloud server that QNAP has partnered with. It would appear that I cannot apply any form of a backup solution using HBS 3 on LAN storage of my own. I have already gone into why I found this irksome so I won't repeat it, but if I am in fact wrong about this I would be happy to be proved as such.
FYI Snapshot replication is available for LUNs.
If this is the case and I would be able to mirror snapshots to a remote share on my LAN, assuming I can perform low-level restores with them this would actually be perferable to managing a separate backup scheme. To be able to perform a full restore onto freshly formatted volume (or a constructed RAID set) from a remote mirror on my LAN is more than I could ask for, really. If this is something Storage Manager can do by design (whether it be to remote share or a remote iSCSI target) please enlighten me as I have not found anything indicating that this is possible without the same requirements as making backups. If I simply was not looking in the right place, then you are in fact correct to be frustated with my tone and I am grateful for you to be taking the time to read this and help me and others who would want to achieve this.

Thanks in advance.
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Re: Connected Remote iSCSI LUNs Unavailable for Use

Post by storageman »

I am not here to be an apologist for Qnap.
I think considering much of their software is included free it is a pretty good deal.
Remote Disk is the function you use for connecting remote ISCSI targets, is that what you've been trying?
The fact that Qnap HBS RTRR doesn't backup to anything other than USB, another Qnap NAS or Cloud is not a biggy for most people (and neither is it a joke!), after all it's free.
Third party tools are available for use if you're not happy with Qnap's. Same snapshot replica, fact it's Qnap only not a big issue either.
Maybe Qnap will consider your feature requests, no idea on that.

Have you tried creating a remote mountpoint share/remote disk and pointing HBS RTRR at it using "Local Backup"? It should fool it into thinking it's local.

Most of my business customers very happy with Qnap.
And in terms of functionality I disagree with you on Synology, no block LUNs there, no tiering, no volume encryption, no cachemount or ZFS models).
The only thing Synology have that Qnap don't is High Availability across two NAS.

If you adopt an aggressive tone, that you wouldn't use face to face, you won't get many responses, here or any other forums.
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Re: Connected Remote iSCSI LUNs Unavailable for Use

Post by DarfNader »

storageman wrote: Tue Oct 08, 2019 9:07 pm I am not here to be an apologist for Qnap.
I think considering much of their software is included free it is a pretty good deal.
I didn't think you were a QNAP shill. I did realize that in your apparent line of work you probably know much more about the product line that I do - maybe ever will - which is why I defer to your experience. I just was surprised that I seemed to be in the minority of those who cared about the conspicuously absent feature that QNAP's first backup tool couldn't use third party volumes on your LAN.

As for the software being "free", I guess it is in the same way that the entertainment software that Tesla provides for their cars is "free". My expectations are that we buy storage "solutions" from vendors like QNAP, Synology, NetApp, or whomever not for the expensive hardware, but for the integrated product. This is both the specialized hardware and software written for it. Therefore, I think it's not unreasonable to have certain expectations about that software, especially if it is heavily marketed to the consumer as a 'comprehensive backup solution'.

To be fair, the reason that chose QNAP over other venders was because of the value proposition QNAP offered, or at least seemed to offer. I didn't want to spend the time building an open source NAS, but time-wise it might not have been a bad idea. With all commercial products, It is rare that features turn out to be as good as they are marketed as, so I tried to measure my expectations. I was initially quite pleased with my purchase of a NAS which I could use as a Plex Media Server. QNAP's NAS functions were for the most part exceptional. However, I found that it took a lot of extra effort to make the Plex Server Software to work properly. For starters, you didn't use the QNAP provided package because it was so old and was not even recommended by Plex. The hardware really struggled transcoding media and the graphics accerlation introduced more problems than it helped with. Finally, as media qualities improved making the transcoding process that much more CPU intensive, I had to use a real computer as my Plex Server. I got the feeling that QNAP's ancillary product packages were mainly repackages of lesser-known subscription service tools or QNAP software that competed with Synology's offerings. I also realized that it was unreasonable for me to expect that a $2000 device (after loading it with drives) could provide high performance NAS services as well as transcode and serve a hi-def Plex stream was expecting too much.
Remote Disk is the function you use for connecting remote ISCSI targets, is that what you've been trying?
Yes: Storage Manager > iSCSI > Remote Disk. I was able to mount the LUN on a third party iSCSI target well enough. It was just that I couldn't seem to do much with that LUN once I mounted it other than see it in FileManager. I was hoping to use it for snapshot replication or a remote backup volume, but I didn't have much luck since remote mounts in FileManager don't appear to be available to any other QNAP apps as far as I could tell.
The fact that Qnap HBS RTRR doesn't backup to anything other than USB, another Qnap NAS or Cloud is not a biggy for most people (and neither is it a joke!), after all it's free.
Third party tools are available for use if you're not happy with Qnap's. Same snapshot replica, fact it's Qnap only not a big issue either.
Maybe Qnap will consider your feature requests, no idea on that.
Backups are as important to people as they choose them to be. Some people don't care about them. Some are fine with syncing instead. I wanted actual backups and I assumed I would be in the majority there. On the other hand, the snapshot tool in Storage Manager is in many ways much better than traditional backups, however I was not comfortable that it didn't protect me against total device failure. I admit I haven't looked beyond QNAPs Storage Manager to perform snapshot mirroring as I don't know enough about how QNAP makes them or how to restore a blank system from them, but I would be very interested to learn how. Whether it is using a third party tool or the "free" software that QNAP provides, as long as it doesn't require that I spend a lot of money to mirror snapshots to volumes on my LAN onto disk which I already own, that's fine with me.
Have you tried creating a remote mountpoint share/remote disk and pointing HBS RTRR at it using "Local Backup"? It should fool it into thinking it's local.
If you mean using the FileManager, as with iSCSI LUNs, remote mounts made there are usable only as QNAP apps allow for. Remote mounts made in HBS 3 appears in FileManager and vice-versa.

However, if you mean making changes to the fstab to "trick" the NAS into thinking the volume is local, I definitely have not as I suspected I could easily break something. If you don't see this as dangerous, it's worth a try.
If you adopt an aggressive tone, that you wouldn't use face to face, you won't get many responses, here or any other forums.
I hope it's apparent that this started with me levelly asking questions and giving examples, not with hostility. I realize that I became frustrated when I found backups to third part volumes on your LAN were not a thing. However, I hope I didn't appear to direct aggression at you or anyone else here. I admit that after commiserating with at least one other person who had a similar gripe, the conversation degenerated into a rant with jokes you probably found unfunny. During venting, hot plasma may be released so you have my apologies if you felt it directed at you. Please know that I do appreciate that you are taking time out of your day to be of assistance to a stranger and I sincerely believe that is an example that we should all follow. I hope that I can be as helpful to others in this context on areas which I have information share.

Thank you.
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Re: Connected Remote iSCSI LUNs Unavailable for Use

Post by storageman »

Not so sure why your so hung up about using LUNs, Qnap's bread and butter is shares. 95%+ buy Qnap/Syno for shares.
ISCSI is an add-on and never has been a key purpose or function of NAS. If you want a ISCSI block, buy a SAN.
People on this forum are trying to run ISCSI on low end 2 and 4 bays, why???
LUN performance is dependent on the host too, not just the Qnap.

Having said that you can point HBS RTRR with versions at a remote disk formatted EXT4 so it doesn't have to be another Qnap.
In this example my LUN was on Syno DS916+
Snapshot Replica you can't use the Remote Disk for that (can't do everything!).

Here's my screenshots:

Syno Target.JPG
Remote Mount Virtual Disk Formtatted EXT4
SynoVirtualDisk.JPG
LUN showing in Shared Folders
DS916LUN.JPG
Source Folder to Backup
LUN in Filestation.JPG
LUN showing in Filestation
backup folder.JPG
HBS pointing at LUN
HBS.JPG
RTRR Files now in LUN after Backup runs
after backup.JPG
One caveat, expansion of the LUN was problematic.
Couldn't get it to recognise additional space when expanding the Synology LUN without starting again. Gave up there/ran out of time.
Flakey Qnap, as I said ISCSI is not their focus and badly tested.
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