Re: [CentOS] Hard drives being renamed

[Miguel Medalha]

>> I've run into this with ZFS on Linux. The 'blkid' is useful to identify the 
>> target device and then add that to your fstab. I don't use device names >> 
>> at all anymore, too ambiguous (depending on the circumstance) in my >> 
>> opinion.

Right. And there are other ways to identify disks unequivocally. Under CentOS, 
for example, I find the following directories:

/dev/disk/by-id
/dev/disk/by-path
/dev/disk/by-uuid

Each one has its optimal use case.

It seems to me that in general the ideal would  be to use the WWN identifier, 
which now comes printed on the disk label sticker and uniquely identifies the 
disk, offering a clear correspondence between physical and logical disks. Under 
CentOS, the WWN ID of detected disks can be found under /dev/disk/by-id. WWN 
stands for "World Wide Name". There's a Wikipedia article about it here:

https://en.wikipedia.org/wiki/World_Wide_Name

"hdparm - I" or even "smartctl  -a" will show which /dev/sdX or whatever 
corresponds to which WWN or other relatively stable ID types. The advantage of 
WWN is that the ID won't change if you connect the disk to a different 
controller, for example from a SAS one to a SATA one. In one of my servers, if 
I unplug a SATA disk from a LSI-Avago SAS controller and I connect it to a 
Intel onboard SATA controller the ID changes from "scsi-idnumber" to 
"ata-brand-model-serialnumber" but the WWN remains constant.
___
CentOS mailing list
CentOS@centos.org
https://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] Hard drives being renamed

[Chris Murphy]

On Tue, May 24, 2016, 3:08 PM Pat Haley  wrote:

>
> Our questions are
>
>   * Has anyone else experienced similar issues?
>   * What can we do to prevent such renaming in the future
>

Yes. You can't, it's non-deterministic. Use fs volume UUID instead, both in
grub.cfg command line for root= parameter and fstab.


Chris Murphy
___
CentOS mailing list
CentOS@centos.org
https://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] Hard drives being renamed

[Leroy Tennison]

- Original Message -
From: "John R Pierce" <pie...@hogranch.com>
To: centos@centos.org
Sent: Tuesday, May 24, 2016 5:04:24 PM
Subject: Re: [CentOS] Hard drives being renamed

On 5/24/2016 2:08 PM, Pat Haley wrote:
>
> We are running Centos 6.7 - 2.6.32-573.22.1.el6.x86_64 on a Quanta 
> Cirrascale, up to date with patches. We have had a couple of instances 
> in which the hard drives have become renamed after reboot (e.g. drive 
> sda is renamed to sdc after reboot).  One time this occurred when we 
> rebooted following the installation of a 10GB NIC card, another time 
> after we tried to install mellanox drivers 
> (MLNX_OFED_LINUX-3.2-2.0.0.0-rhel6.7-x86_64). Currently we are unable 
> to boot because that drive has been renamed.
>
> Our questions are
>
>  * Has anyone else experienced similar issues?
>  * What can we do to prevent such renaming in the future 


don't use device names in your fstab, use labels, or use LVM, or whatever.



-- 
john r pierce, recycling bits in santa cruz

Use blkid to get the UUIDs then use UUID="..." in fstab.  Be aware that nothing 
is failsafe, changing filesystems on a partition will change the UUID and "dd 
ing" a partition to another drive but leaving it in the system without manually 
changing the UUID of one of the partitions will result in duplicate UUIDs and 
corresponding confusion - "been there, done that".

___
CentOS mailing list
CentOS@centos.org
https://lists.centos.org/mailman/listinfo/centos

Confidentiality Notice | This email and any included attachments may be 
privileged, confidential and/or otherwise protected from disclosure.  Access to 
this email by anyone other than the intended recipient is unauthorized.  If you 
believe you have received this email in error, please contact the sender 
immediately and delete all copies.  If you are not the intended recipient, you 
are notified that disclosing, copying, distributing or taking any action in 
reliance on the contents of this information is strictly prohibited.
___
CentOS mailing list
CentOS@centos.org
https://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] Hard drives being renamed

[J Wilder]

I've run into this with ZFS on Linux. The 'blkid' is useful to identify the
target device and then add that to your fstab. I don't use device names at
all anymore, too ambiguous (depending on the circumstance) in my opinion.

On Tue, May 24, 2016 at 3:04 PM, John R Pierce  wrote:

> On 5/24/2016 2:08 PM, Pat Haley wrote:
>
>>
>> We are running Centos 6.7 - 2.6.32-573.22.1.el6.x86_64 on a Quanta
>> Cirrascale, up to date with patches. We have had a couple of instances in
>> which the hard drives have become renamed after reboot (e.g. drive sda is
>> renamed to sdc after reboot).  One time this occurred when we rebooted
>> following the installation of a 10GB NIC card, another time after we tried
>> to install mellanox drivers (MLNX_OFED_LINUX-3.2-2.0.0.0-rhel6.7-x86_64).
>> Currently we are unable to boot because that drive has been renamed.
>>
>> Our questions are
>>
>>  * Has anyone else experienced similar issues?
>>  * What can we do to prevent such renaming in the future
>>
>
>
> don't use device names in your fstab, use labels, or use LVM, or whatever.
>
>
>
> --
> john r pierce, recycling bits in santa cruz
>
>
> ___
> CentOS mailing list
> CentOS@centos.org
> https://lists.centos.org/mailman/listinfo/centos
>
___
CentOS mailing list
CentOS@centos.org
https://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] Hard drives being renamed

[John R Pierce]

On 5/24/2016 2:08 PM, Pat Haley wrote:


We are running Centos 6.7 - 2.6.32-573.22.1.el6.x86_64 on a Quanta 
Cirrascale, up to date with patches. We have had a couple of instances 
in which the hard drives have become renamed after reboot (e.g. drive 
sda is renamed to sdc after reboot).  One time this occurred when we 
rebooted following the installation of a 10GB NIC card, another time 
after we tried to install mellanox drivers 
(MLNX_OFED_LINUX-3.2-2.0.0.0-rhel6.7-x86_64). Currently we are unable 
to boot because that drive has been renamed.


Our questions are

 * Has anyone else experienced similar issues?
 * What can we do to prevent such renaming in the future 



don't use device names in your fstab, use labels, or use LVM, or whatever.



--
john r pierce, recycling bits in santa cruz

___
CentOS mailing list
CentOS@centos.org
https://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] Hard drives being renamed

[m . roth]

Pat Haley wrote:
>
> We are running Centos 6.7 - 2.6.32-573.22.1.el6.x86_64 on a Quanta
> Cirrascale, up to date with patches. We have had a couple of instances
> in which the hard drives have become renamed after reboot (e.g. drive
> sda is renamed to sdc after reboot).  One time this occurred when we
> rebooted following the installation of a 10GB NIC card, another time
> after we tried to install mellanox drivers
> (MLNX_OFED_LINUX-3.2-2.0.0.0-rhel6.7-x86_64). Currently we are unable to
> boot because that drive has been renamed.
>
> Our questions are
>
>   * Has anyone else experienced similar issues?
>   * What can we do to prevent such renaming in the future
>
In the past. To resolve you could use (*UGH*) the
no-possible-way-to-remember UUID, or you could label the filesystems, and
refer to them that way. I strongly prefer the latter.

___
CentOS mailing list
CentOS@centos.org
https://lists.centos.org/mailman/listinfo/centos

[CentOS] Hard drives being renamed

[Pat Haley]

Hi,

We are running Centos 6.7 - 2.6.32-573.22.1.el6.x86_64 on a Quanta 
Cirrascale, up to date with patches. We have had a couple of instances 
in which the hard drives have become renamed after reboot (e.g. drive 
sda is renamed to sdc after reboot).  One time this occurred when we 
rebooted following the installation of a 10GB NIC card, another time 
after we tried to install mellanox drivers 
(MLNX_OFED_LINUX-3.2-2.0.0.0-rhel6.7-x86_64). Currently we are unable to 
boot because that drive has been renamed.


Our questions are

 * Has anyone else experienced similar issues?
 * What can we do to prevent such renaming in the future

--

-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Pat Haley  Email:  pha...@mit.edu
Center for Ocean Engineering   Phone:  (617) 253-6824
Dept. of Mechanical EngineeringFax:(617) 253-8125
MIT, Room 5-213http://web.mit.edu/phaley/www/
77 Massachusetts Avenue
Cambridge, MA  02139-4301

___
CentOS mailing list
CentOS@centos.org
https://lists.centos.org/mailman/listinfo/centos