Very strange issue with iSCSI

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gdestefano
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Very strange issue with iSCSI

Post by gdestefano »

Hi,
I have a QNAP TS-469 Pro RAId 5 (fw 4.3.4.0644) connected in iSCSI to a windows 2012 server through a Cisco Catalyst 4510R using 802.3ad like this MPIO configuration :geek: :

https://www.imageupload.co.uk/images/20 ... attura.jpg

The only difference is that they are not connected to two different switch but to two different modules of the same switch, the NAS has 2 LUN and I have connected both like above to the server.
The I/O speed is acceptable (consider 1 GB ethernet) perhaps writing is a little bit slower then I aspected (80 MB/s instead of 110 MB/s), anyway the strange think is
that when I do a copy from/to the server simultaneously on each LUN the first started process gets stopped writing/reading until the second one finished! :(

https://www.imageupload.co.uk/image/TDqW

Is there something wrong? :S

Very thanks!
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storageman
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Re: Very strange issue with iSCSI

Post by storageman »

Create a different target for each LUN
gdestefano
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Re: Very strange issue with iSCSI

Post by gdestefano »

I have already done tihs... on the server there are 2 iSCSI target one for each LUN.
As you can see in the second link they are G: and E:
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storageman
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Re: Very strange issue with iSCSI

Post by storageman »

The same target name-01, name-02 or a completely different names name1-01, name2-01. The NAS itself needs have to two differently named targets.
If you copy to the other LUN from a different server does the same thing happen?
Otherwise if that doesn't work might be box just aint fast enough!
gdestefano
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Re: Very strange issue with iSCSI

Post by gdestefano »

This is the iSCSI Initiator Report on the server:

Target #0
========
Target name = iqn.2004-04.com.qnap:ts-469pro:iscsi.be2014.d4bd40
Session Details
===============
Session #1
===========
Number of Connections = 1

Connection #1
==============
Target Address = 10.0.0.27
Target Port = 3260
#0. Disk 4
========
Address:Port 5: Bus 0: Target 2: LUN 0
Session #2
===========
Number of Connections = 1

Connection #1
==============
Target Address = 10.0.0.27
Target Port = 3260
#0. Disk 4
========
Address:Port 5: Bus 0: Target 3: LUN 0
Target #1
========
Target name = iqn.2004-04.com.qnap:ts-469pro:iscsi.be16.d4bd40
Session Details
===============
Session #1
===========
Number of Connections = 1

Connection #1
==============
Target Address = 10.0.0.27
Target Port = 3260
#0. Disk 3
========
Address:Port 5: Bus 0: Target 0: LUN 0
Session #2
===========
Number of Connections = 1

Connection #1
==============
Target Address = 10.0.0.27
Target Port = 3260
#0. Disk 3
========
Address:Port 5: Bus 0: Target 1: LUN 0

and this that on the QNAP:
https://www.imageupload.co.uk/image/TDwR
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storageman
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Re: Very strange issue with iSCSI

Post by storageman »

Yes two targets, don't know then.
Out of interest why not one LUN with separate folders for each backup job.
Perhaps you can run two jobs concurrently that way.
gdestefano
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Re: Very strange issue with iSCSI

Post by gdestefano »

One target is for normal backup and the other is for deduplication...

Can you help us to understand what the problem is having some other information?
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storageman
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Re: Very strange issue with iSCSI

Post by storageman »

gdestefano wrote:One target is for normal backup and the other is for deduplication...
How does that matter? They would be in separate shares.

Sorry, no idea, if you don't like it why not use shares.

Is the LUN thick or thin? I would use block thick to avoid tidy up issues.
gdestefano
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Re: Very strange issue with iSCSI

Post by gdestefano »

If I disconnect both iSCSI from this server and reconnect to another that have 2008 R2 this issue not happens!
gdestefano
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Re: Very strange issue with iSCSI

Post by gdestefano »

gdestefano wrote:If I disconnect both iSCSI from this server and reconnect to another that have 2008 R2 this issue not happens!
I have also tried on a server with the samo OS (2012) and it works perfectly... maybe there's a hardware problem? :?:
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