Re: udevadm question

2016-08-25 Thread Mark Post 
>>> On 8/25/2016 at 01:25 PM, Mark Pace  wrote: 

> But I don't have a multipath.conf file.  I don't have anything to use as a
> template to create this file.

Look under /usr/share/doc/packages/multipath-tools/ for
multipath.conf.annotated
multipath.conf.defaults

Or, man multipath.conf

As a side note, if you don't have the findutils-locate package installed, it 
can help with things like this.

# locate multipath.conf
/usr/share/doc/packages/multipath-tools/multipath.conf.annotated
/usr/share/doc/packages/multipath-tools/multipath.conf.defaults
/usr/share/doc/packages/multipath-tools/multipath.conf.synthetic
/usr/share/man/man5/multipath.conf.5.gz


Mark Post

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Re: udevadm question

2016-08-25 Thread Mark Pace 
On Thu, Aug 25, 2016 at 1:10 PM, Steffen Maier 
wrote:

> On 08/25/2016 06:53 PM, Mark Pace wrote:
>
>> I'm having issues with that link also.
>>
>> *To enable user-friendly names or to specify aliases:*
>>
>> *In a terminal console, log in as the root user.*
>>
>> *Open the /etc/multipath.conf file in a text editor.*
>>
>> *(Optional) Modify the location of the /var/lib/multipath/bindings file. *
>>
>> *The alternate path must be available on the system root device where
>> multipath can find it. *
>>
>
> Does your multipath volume contain your root-fs?
> If not, you can definitely skip this optional step.
>

No this new multipath is going to be used as a data devive


>
> *Move the /var/lib/multipath/bindings file to /etc/multipath/bindings.*
>>
>> *Set the bindings_file option in the defaults section of
>> /etc/multipath.conf to this new location. For example:*
>> On my system I don't have any of those files.
>> /etc/multipath.conf
>> /var/lib/multipath <-- that subdirectory does exist in /var/lib
>>
>
> The only relevant step for simple data volumes is
> "5. (Optional) Specify your own names for devices by using the alias
> option in the multipath section."
> (and 6 to save the changes)
>

But I don't have a multipath.conf file.  I don't have anything to use as a
template to create this file.


>
> On Thu, Aug 25, 2016 at 12:33 PM, Mark Pace 
>> wrote:
>>
>> Thank you for the comments and the link.  I'll go looking there.
>>>
>>> The manual I refer to is - SC33-8413-08 - How to use FC-attached SCSI
>>> devices with Linux on z Systems
>>>
>>
> OK, thanks for letting me know.
>
> Parts of this book are superseded by the more often updated
> "Device Drivers, Features, and Commands" book
> or respective distro documentation (for the case here).
>
>
>
> --
> Mit freundlichen Grüßen / Kind regards
> Steffen Maier
>
> Linux on z Systems Development
>
> IBM Deutschland Research & Development GmbH
> Vorsitzende des Aufsichtsrats: Martina Koederitz
> Geschaeftsfuehrung: Dirk Wittkopp
> Sitz der Gesellschaft: Boeblingen
> Registergericht: Amtsgericht Stuttgart, HRB 243294
>
> --
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> http://wiki.linuxvm.org/
>



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Re: udevadm question

2016-08-25 Thread Steffen Maier 

On 08/25/2016 06:53 PM, Mark Pace wrote:

I'm having issues with that link also.

*To enable user-friendly names or to specify aliases:*

*In a terminal console, log in as the root user.*

*Open the /etc/multipath.conf file in a text editor.*

*(Optional) Modify the location of the /var/lib/multipath/bindings file. *

*The alternate path must be available on the system root device where
multipath can find it. *


Does your multipath volume contain your root-fs?
If not, you can definitely skip this optional step.


*Move the /var/lib/multipath/bindings file to /etc/multipath/bindings.*

*Set the bindings_file option in the defaults section of
/etc/multipath.conf to this new location. For example:*
On my system I don't have any of those files.
/etc/multipath.conf
/var/lib/multipath <-- that subdirectory does exist in /var/lib


The only relevant step for simple data volumes is
"5. (Optional) Specify your own names for devices by using the alias 
option in the multipath section."

(and 6 to save the changes)


On Thu, Aug 25, 2016 at 12:33 PM, Mark Pace  wrote:


Thank you for the comments and the link.  I'll go looking there.

The manual I refer to is - SC33-8413-08 - How to use FC-attached SCSI
devices with Linux on z Systems


OK, thanks for letting me know.

Parts of this book are superseded by the more often updated
"Device Drivers, Features, and Commands" book
or respective distro documentation (for the case here).


--
Mit freundlichen Grüßen / Kind regards
Steffen Maier

Linux on z Systems Development

IBM Deutschland Research & Development GmbH
Vorsitzende des Aufsichtsrats: Martina Koederitz
Geschaeftsfuehrung: Dirk Wittkopp
Sitz der Gesellschaft: Boeblingen
Registergericht: Amtsgericht Stuttgart, HRB 243294

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Re: udevadm question

2016-08-25 Thread Mark Pace 
I'm having issues with that link also.

*To enable user-friendly names or to specify aliases:*
-

*In a terminal console, log in as the root user.*
-

*Open the /etc/multipath.conf file in a text editor.*

*(Optional) Modify the location of the /var/lib/multipath/bindings file. *

*The alternate path must be available on the system root device where
multipath can find it. *
-

*Move the /var/lib/multipath/bindings file to /etc/multipath/bindings.*

*Set the bindings_file option in the defaults section of
/etc/multipath.conf to this new location. For example:*
On my system I don't have any of those files.
/etc/multipath.conf
/var/lib/multipath <-- that subdirectory does exist in /var/lib



On Thu, Aug 25, 2016 at 12:33 PM, Mark Pace  wrote:

> Thank you for the comments and the link.  I'll go looking there.
>
> The manual I refer to is - SC33-8413-08 - How to use FC-attached SCSI
> devices with
> Linux on z Systems
>
>
> On Thu, Aug 25, 2016 at 12:27 PM, Steffen Maier 
> wrote:
>
>> Hi Mark,
>>
>> On 08/25/2016 06:20 PM, Mark Pace wrote:
>>
>>> sles 11sp3
>>>
>>> Working with FCP devices for the first time.
>>> I have 2 devices that I am using to multipath.
>>> I've followed the manual pretty well to multipath these devices.
>>>
>>>  multipath -ll
>>>
>>
>> multipathd -k'show topo'
>> is preferred because
>> - it only works if multipathd runs which is a requirement
>> - it does not cause unnecessary load due to extra path checks
>>
>> 36005076307ffd4da0028 dm-1 IBM,2107900
>>> size=100G features='1 queue_if_no_path' hwhandler='0' wp=rw
>>> `-+- policy='service-time 0' prio=1 status=active
>>>   |- 0:0:0:1076379648 sda 8:0  active ready running
>>>   `- 1:0:0:1076379648 sdb 8:16 active ready running
>>>
>>> So now I have this device with the really long name -
>>> /dev/mapper/36005076307ffd4da0028
>>> /dev/mapper/36005076307ffd4da0028_part1
>>>
>>> In the manual it talks about using udev to map it to a more friendly
>>> name,
>>> there it goes wrong. The manual talks about udevinfo, which doesn't
>>> exist,
>>> it's part of udevadm, but that output doesn't look like the manual.
>>>
>>> I'm looking for example of udevadm to add a rule to rename those to
>>> something short and easy to remember.
>>>
>>
>> Which manual do you refer to?
>>
>> While udev can be used in general to rename devices,
>> for multipath devices there is a much easier common way to do this via
>> alias names in multipath.conf:
>> https://www.suse.com/documentation/sles11/stor_admin/data/mpionames.html
>>
>> --
>> Mit freundlichen Grüßen / Kind regards
>> Steffen Maier
>>
>> Linux on z Systems Development
>>
>> IBM Deutschland Research & Development GmbH
>> Vorsitzende des Aufsichtsrats: Martina Koederitz
>> Geschaeftsfuehrung: Dirk Wittkopp
>> Sitz der Gesellschaft: Boeblingen
>> Registergericht: Amtsgericht Stuttgart, HRB 243294
>>
>> --
>> For LINUX-390 subscribe / signoff / archive access instructions,
>> send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or
>> visit
>> http://www.marist.edu/htbin/wlvindex?LINUX-390
>> --
>> For more information on Linux on System z, visit
>> http://wiki.linuxvm.org/
>>
>
>
>
> --
> The postings on this site are my own and don’t necessarily represent
> Mainline’s positions or opinions
>
> Mark D Pace
> Senior Systems Engineer
> Mainline Information Systems
>
>
>
>


-- 
The postings on this site are my own and don’t necessarily represent
Mainline’s positions or opinions

Mark D Pace
Senior Systems Engineer
Mainline Information Systems

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Re: udevadm question

2016-08-25 Thread Mark Pace 
Thank you for the comments and the link.  I'll go looking there.

The manual I refer to is - SC33-8413-08 - How to use FC-attached SCSI
devices with
Linux on z Systems


On Thu, Aug 25, 2016 at 12:27 PM, Steffen Maier 
wrote:

> Hi Mark,
>
> On 08/25/2016 06:20 PM, Mark Pace wrote:
>
>> sles 11sp3
>>
>> Working with FCP devices for the first time.
>> I have 2 devices that I am using to multipath.
>> I've followed the manual pretty well to multipath these devices.
>>
>>  multipath -ll
>>
>
> multipathd -k'show topo'
> is preferred because
> - it only works if multipathd runs which is a requirement
> - it does not cause unnecessary load due to extra path checks
>
> 36005076307ffd4da0028 dm-1 IBM,2107900
>> size=100G features='1 queue_if_no_path' hwhandler='0' wp=rw
>> `-+- policy='service-time 0' prio=1 status=active
>>   |- 0:0:0:1076379648 sda 8:0  active ready running
>>   `- 1:0:0:1076379648 sdb 8:16 active ready running
>>
>> So now I have this device with the really long name -
>> /dev/mapper/36005076307ffd4da0028
>> /dev/mapper/36005076307ffd4da0028_part1
>>
>> In the manual it talks about using udev to map it to a more friendly name,
>> there it goes wrong. The manual talks about udevinfo, which doesn't exist,
>> it's part of udevadm, but that output doesn't look like the manual.
>>
>> I'm looking for example of udevadm to add a rule to rename those to
>> something short and easy to remember.
>>
>
> Which manual do you refer to?
>
> While udev can be used in general to rename devices,
> for multipath devices there is a much easier common way to do this via
> alias names in multipath.conf:
> https://www.suse.com/documentation/sles11/stor_admin/data/mpionames.html
>
> --
> Mit freundlichen Grüßen / Kind regards
> Steffen Maier
>
> Linux on z Systems Development
>
> IBM Deutschland Research & Development GmbH
> Vorsitzende des Aufsichtsrats: Martina Koederitz
> Geschaeftsfuehrung: Dirk Wittkopp
> Sitz der Gesellschaft: Boeblingen
> Registergericht: Amtsgericht Stuttgart, HRB 243294
>
> --
> For LINUX-390 subscribe / signoff / archive access instructions,
> send email to lists...@vm.marist.edu with the message: INFO LINUX-390 or
> visit
> http://www.marist.edu/htbin/wlvindex?LINUX-390
> --
> For more information on Linux on System z, visit
> http://wiki.linuxvm.org/
>



-- 
The postings on this site are my own and don’t necessarily represent
Mainline’s positions or opinions

Mark D Pace
Senior Systems Engineer
Mainline Information Systems

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Re: udevadm question

2016-08-25 Thread Steffen Maier 

Hi Mark,

On 08/25/2016 06:20 PM, Mark Pace wrote:

sles 11sp3

Working with FCP devices for the first time.
I have 2 devices that I am using to multipath.
I've followed the manual pretty well to multipath these devices.

 multipath -ll


multipathd -k'show topo'
is preferred because
- it only works if multipathd runs which is a requirement
- it does not cause unnecessary load due to extra path checks


36005076307ffd4da0028 dm-1 IBM,2107900
size=100G features='1 queue_if_no_path' hwhandler='0' wp=rw
`-+- policy='service-time 0' prio=1 status=active
  |- 0:0:0:1076379648 sda 8:0  active ready running
  `- 1:0:0:1076379648 sdb 8:16 active ready running

So now I have this device with the really long name -
/dev/mapper/36005076307ffd4da0028
/dev/mapper/36005076307ffd4da0028_part1

In the manual it talks about using udev to map it to a more friendly name,
there it goes wrong. The manual talks about udevinfo, which doesn't exist,
it's part of udevadm, but that output doesn't look like the manual.

I'm looking for example of udevadm to add a rule to rename those to
something short and easy to remember.


Which manual do you refer to?

While udev can be used in general to rename devices,
for multipath devices there is a much easier common way to do this via 
alias names in multipath.conf:

https://www.suse.com/documentation/sles11/stor_admin/data/mpionames.html

--
Mit freundlichen Grüßen / Kind regards
Steffen Maier

Linux on z Systems Development

IBM Deutschland Research & Development GmbH
Vorsitzende des Aufsichtsrats: Martina Koederitz
Geschaeftsfuehrung: Dirk Wittkopp
Sitz der Gesellschaft: Boeblingen
Registergericht: Amtsgericht Stuttgart, HRB 243294

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udevadm question

2016-08-25 Thread Mark Pace 
sles 11sp3

Working with FCP devices for the first time.
I have 2 devices that I am using to multipath.
I've followed the manual pretty well to multipath these devices.

 multipath -ll
36005076307ffd4da0028 dm-1 IBM,2107900
size=100G features='1 queue_if_no_path' hwhandler='0' wp=rw
`-+- policy='service-time 0' prio=1 status=active
  |- 0:0:0:1076379648 sda 8:0  active ready running
  `- 1:0:0:1076379648 sdb 8:16 active ready running

So now I have this device with the really long name -
/dev/mapper/36005076307ffd4da0028
/dev/mapper/36005076307ffd4da0028_part1

In the manual it talks about using udev to map it to a more friendly name,
there it goes wrong. The manual talks about udevinfo, which doesn't exist,
it's part of udevadm, but that output doesn't look like the manual.

I'm looking for example of udevadm to add a rule to rename those to
something short and easy to remember.


-- 
The postings on this site are my own and don’t necessarily represent
Mainline’s positions or opinions

Mark D Pace
Senior Systems Engineer
Mainline Information Systems

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Re: Creating root LVM

2016-08-25 Thread Michael Weiner 
Thanks for the feedback all!

Sent from my iPhone

> On Aug 25, 2016, at 10:34, Grzegorz Powiedziuk  wrote:
> 
> We have lvroots on all our systems, in the past we had root without lvm and
> honestly in both scenarios there always was a way to get to the data in
> case of problems of course if all devices were available.
> 
> But it is always good to have unique vgnames  (we do hostname_vgroot for
> example).
> LVM actually made some migrations between different storage systems easier
> (but that was FCP). Thanks to lvm we didn't have to worry about some
> aspects (mounts were always referring to /dev/mapper/vgname-lvname etc no
> matter what the underlying device names were)
> 
> boot I still usually leave outside of LVM
> 
> Greg
> 
> 
> 
> 
> 
> 2016-08-23 21:20 GMT+02:00 Robert J Brenneman :
> 
>> It depends on what you consider to be the bigger problem.
>> 
>> A) having to care upfront about what needs space where is hard. Make / one
>> huge logical volume and don't worry about space until you need more, then
>> just grow / online.
>> 
>> B) fixing a machine that won't boot is hard. When /'s contents are smeared
>> across multiple devices it is tough to get the machine to a working state
>> again, often requiring the service of a dedicated emergency rescue system.
>> 
>> Note that this is further complicated by cloud management tools that impose
>> their own restrictions on system disk layouts. It seems like no matter what
>> you prefer, your cloud tools won't handle your chosen file system layout
>> unless you like one big vanilla / partition with ext3 and no lvm at all.
>> 
>>> On Tue, Aug 23, 2016, 13:26 Donald Russell  wrote:
>>> 
>>> We have rhel5 with rootvg and rootlv. That caused us some grief when a
>> root
>>> password was lost and we "simply wanted to mount it on another system".
>>> Not so fast there skippy, all the systems have rootvg/lv so we had to
>> work
>>> around that... (Not rocket science, but inconvenient)
>>> 
>>> Now, (upgrading to rehl7) we put the "basic Linux system" on a
>>> simple-to-use Mod-9 and use LVM for application file systems and a few
>>> others.  Now it's very simple to mount that / file system on another
>> server
>>> if necessary.
>>> 
>>> 
>>> 
>>> 
>>> 
>>> On Tuesday, August 23, 2016, Michael Weiner 
>>> wrote:
>>> 
 Good morning all,
 
 I was having a little debate yesterday and I want to get the experts on
 this list opinions.
 
 What's the best practice when it comes to the root directory?
 
 Is it acceptable and recommend to create an vgroot and lvroot so it is
 expandable?
 
 Or is it recommended to have the root directory as a regular directory
>>> and
 not expandable.
 
 Thank you!
 
 
 Sent from my iPhone
 
 
 Sent from my iPhone
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>>> 
>>> 
>>> --
>>> Sent from iPhone Gmail Mobile
>>> 
>>> --
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>>> http://wiki.linuxvm.org/
>> 
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> 
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Re: Creating root LVM

2016-08-25 Thread Grzegorz Powiedziuk 
We have lvroots on all our systems, in the past we had root without lvm and
honestly in both scenarios there always was a way to get to the data in
case of problems of course if all devices were available.

But it is always good to have unique vgnames  (we do hostname_vgroot for
example).
LVM actually made some migrations between different storage systems easier
(but that was FCP). Thanks to lvm we didn't have to worry about some
aspects (mounts were always referring to /dev/mapper/vgname-lvname etc no
matter what the underlying device names were)

boot I still usually leave outside of LVM

Greg





2016-08-23 21:20 GMT+02:00 Robert J Brenneman :

> It depends on what you consider to be the bigger problem.
>
> A) having to care upfront about what needs space where is hard. Make / one
> huge logical volume and don't worry about space until you need more, then
> just grow / online.
>
> B) fixing a machine that won't boot is hard. When /'s contents are smeared
> across multiple devices it is tough to get the machine to a working state
> again, often requiring the service of a dedicated emergency rescue system.
>
> Note that this is further complicated by cloud management tools that impose
> their own restrictions on system disk layouts. It seems like no matter what
> you prefer, your cloud tools won't handle your chosen file system layout
> unless you like one big vanilla / partition with ext3 and no lvm at all.
>
> On Tue, Aug 23, 2016, 13:26 Donald Russell  wrote:
>
> > We have rhel5 with rootvg and rootlv. That caused us some grief when a
> root
> > password was lost and we "simply wanted to mount it on another system".
> > Not so fast there skippy, all the systems have rootvg/lv so we had to
> work
> > around that... (Not rocket science, but inconvenient)
> >
> > Now, (upgrading to rehl7) we put the "basic Linux system" on a
> > simple-to-use Mod-9 and use LVM for application file systems and a few
> > others.  Now it's very simple to mount that / file system on another
> server
> > if necessary.
> >
> >
> >
> >
> >
> > On Tuesday, August 23, 2016, Michael Weiner 
> > wrote:
> >
> > > Good morning all,
> > >
> > > I was having a little debate yesterday and I want to get the experts on
> > > this list opinions.
> > >
> > > What's the best practice when it comes to the root directory?
> > >
> > > Is it acceptable and recommend to create an vgroot and lvroot so it is
> > > expandable?
> > >
> > > Or is it recommended to have the root directory as a regular directory
> > and
> > > not expandable.
> > >
> > > Thank you!
> > >
> > >
> > > Sent from my iPhone
> > >
> > >
> > > Sent from my iPhone
> > > --
> > > For LINUX-390 subscribe / signoff / archive access instructions,
> > > send email to lists...@vm.marist.edu  with the message:
> > > INFO LINUX-390 or visit
> > > http://www.marist.edu/htbin/wlvindex?LINUX-390
> > > --
> > > For more information on Linux on System z, visit
> > > http://wiki.linuxvm.org/
> > >
> >
> >
> > --
> > Sent from iPhone Gmail Mobile
> >
> > --
> > For LINUX-390 subscribe / signoff / archive access instructions,
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> > visit
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> >
>
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