Hi all,
I have the following situation.
Source file system: an AIX volume created on hundreds of very small LUNs (HDS storage array, something like 15 GB each!) Destination file system: a "mirrored" one to online migrate using LVM with no disruption on services but at the same time consolidating on a single LUN on NetApp (as you know the geometry is completely different!)
In the past I did it but on a 1:1 relationship between source and destination LUNs. Not there's somebody stating that on AIX this is not possible... ?!? But this is possibile on any distribution of Linux too!!!
My idea in other words is to map the new space to the same AIX host that will use to create a sort of R1 between file systems (Veritas Volume Manager also doed this i.e) regards
Hello Milazzo,
this will work (did that quite a few times in the past), but AIX is going to be nasty here, because when you create volume groups, you need to define parameters for maximum logical volumes in a vg and that limits the size of the logical volumes, so you might end up migrating the data two times.
We had the same situation where our previous storage guy thought that slicing a 500gb Lun into a gazillion pieces increases performance and so we had about 50 10GB sized LUNs in one volume group for just one filesystem. To migrate the data without disruption we had to go for some intermediate steps like 10*50 first, then adapt the volume group parameters, then migrate to 2*250 and finally to 1*500 - YMMV here, depending on the configuration of your volume group.
Bye,
Alexander Griesser
System-Administrator
ANEXIA Internetdienstleistungs GmbH
Telefon: +43-463-208501-320
Telefax: +43-463-208501-500
E-Mail: ag@anexia.at
Web: http://www.anexia.at
Anschrift Hauptsitz Klagenfurt: Feldkirchnerstraße 140, 9020 Klagenfurt
Geschäftsführer: Alexander Windbichler
Firmenbuch: FN 289918a | Gerichtsstand: Klagenfurt | UID-Nummer: AT U63216601
Von: toasters-bounces@teaparty.net [mailto:toasters-bounces@teaparty.net] Im Auftrag von Milazzo Giacomo Gesendet: Freitag, 18. Mai 2012 14:05 An: toasters@teaparty.net Betreff: LUN migration and consolidation
Hi all,
I have the following situation.
Source file system: an AIX volume created on hundreds of very small LUNs (HDS storage array, something like 15 GB each!)
Destination file system: a "mirrored" one to online migrate using LVM with no disruption on services but at the same time consolidating on a single LUN on NetApp (as you know the geometry is completely different!)
In the past I did it but on a 1:1 relationship between source and destination LUNs.
Not there's somebody stating that on AIX this is not possible... ?!? But this is possibile on any distribution of Linux too!!!
My idea in other words is to map the new space to the same AIX host that will use to create a sort of R1 between file systems (Veritas Volume Manager also doed this i.e)
regards
Hi Alexander,
this is very good answer. Thanks a lot. I will take into consideration your warnings about volume groups parameters.
Regards
Da: Alexander Griesser [mailto:ag@anexia.at] Inviato: venerdì 18 maggio 2012 14:33 A: Milazzo Giacomo; toasters@teaparty.net Oggetto: AW: LUN migration and consolidation
Hello Milazzo,
this will work (did that quite a few times in the past), but AIX is going to be nasty here, because when you create volume groups, you need to define parameters for maximum logical volumes in a vg and that limits the size of the logical volumes, so you might end up migrating the data two times. We had the same situation where our previous storage guy thought that slicing a 500gb Lun into a gazillion pieces increases performance and so we had about 50 10GB sized LUNs in one volume group for just one filesystem. To migrate the data without disruption we had to go for some intermediate steps like 10*50 first, then adapt the volume group parameters, then migrate to 2*250 and finally to 1*500 - YMMV here, depending on the configuration of your volume group.
Bye,
Alexander Griesser System-Administrator
ANEXIA Internetdienstleistungs GmbH
Telefon: +43-463-208501-320 Telefax: +43-463-208501-500
E-Mail: ag@anexia.atmailto:ag@anexia.at Web: http://www.anexia.at
Anschrift Hauptsitz Klagenfurt: Feldkirchnerstraße 140, 9020 Klagenfurt Geschäftsführer: Alexander Windbichler Firmenbuch: FN 289918a | Gerichtsstand: Klagenfurt | UID-Nummer: AT U63216601
Von: toasters-bounces@teaparty.netmailto:toasters-bounces@teaparty.net [mailto:toasters-bounces@teaparty.net]mailto:[mailto:toasters-bounces@teaparty.net] Im Auftrag von Milazzo Giacomo Gesendet: Freitag, 18. Mai 2012 14:05 An: toasters@teaparty.netmailto:toasters@teaparty.net Betreff: LUN migration and consolidation
Hi all,
I have the following situation.
Source file system: an AIX volume created on hundreds of very small LUNs (HDS storage array, something like 15 GB each!) Destination file system: a "mirrored" one to online migrate using LVM with no disruption on services but at the same time consolidating on a single LUN on NetApp (as you know the geometry is completely different!)
In the past I did it but on a 1:1 relationship between source and destination LUNs. Not there's somebody stating that on AIX this is not possible... ?!? But this is possibile on any distribution of Linux too!!!
My idea in other words is to map the new space to the same AIX host that will use to create a sort of R1 between file systems (Veritas Volume Manager also doed this i.e) regards
This limit should rarely become a problem. It was a barrier in the early days, but you can use the -t option to increase the maximum PVs per VG with a chvg -t. You can do this any time.
From: toasters-bounces@teaparty.net [mailto:toasters-bounces@teaparty.net] On Behalf Of Alexander Griesser Sent: Friday, May 18, 2012 1:33 PM To: Milazzo Giacomo; toasters@teaparty.net Subject: AW: LUN migration and consolidation
Hello Milazzo,
this will work (did that quite a few times in the past), but AIX is going to be nasty here, because when you create volume groups, you need to define parameters for maximum logical volumes in a vg and that limits the size of the logical volumes, so you might end up migrating the data two times. We had the same situation where our previous storage guy thought that slicing a 500gb Lun into a gazillion pieces increases performance and so we had about 50 10GB sized LUNs in one volume group for just one filesystem. To migrate the data without disruption we had to go for some intermediate steps like 10*50 first, then adapt the volume group parameters, then migrate to 2*250 and finally to 1*500 - YMMV here, depending on the configuration of your volume group.
Bye,
Alexander Griesser System-Administrator
ANEXIA Internetdienstleistungs GmbH
Telefon: +43-463-208501-320 Telefax: +43-463-208501-500
E-Mail: ag@anexia.atmailto:ag@anexia.at Web: http://www.anexia.at
Anschrift Hauptsitz Klagenfurt: Feldkirchnerstraße 140, 9020 Klagenfurt Geschäftsführer: Alexander Windbichler Firmenbuch: FN 289918a | Gerichtsstand: Klagenfurt | UID-Nummer: AT U63216601
Von: toasters-bounces@teaparty.net [mailto:toasters-bounces@teaparty.net] Im Auftrag von Milazzo Giacomo Gesendet: Freitag, 18. Mai 2012 14:05 An: toasters@teaparty.net Betreff: LUN migration and consolidation
Hi all,
I have the following situation.
Source file system: an AIX volume created on hundreds of very small LUNs (HDS storage array, something like 15 GB each!) Destination file system: a "mirrored" one to online migrate using LVM with no disruption on services but at the same time consolidating on a single LUN on NetApp (as you know the geometry is completely different!)
In the past I did it but on a 1:1 relationship between source and destination LUNs. Not there's somebody stating that on AIX this is not possible... ?!? But this is possibile on any distribution of Linux too!!!
My idea in other words is to map the new space to the same AIX host that will use to create a sort of R1 between file systems (Veritas Volume Manager also doed this i.e) regards
-
Alexander Griesser -
Milazzo Giacomo -
Steiner, Jeffrey