FAQ Search Today's Posts Mark Forums Read
» Video Reviews

» Linux Archive

Linux-archive is a website aiming to archive linux email lists and to make them easily accessible for linux users/developers.


» Sponsor

» Partners

» Sponsor

Go Back   Linux Archive > CentOS > CentOS

 
 
LinkBack Thread Tools
 
Old 06-18-2012, 05:35 PM
Les Mikesell
 
Default Best way to duplicate a live Centos 5 server?

On Mon, Jun 18, 2012 at 11:21 AM, Cal Sawyer <cal-s@blue-bolt.com> wrote:
>
> ReaR has suddenly become very interesting to me, probably explaining why
> it utterly fails to work properly (for me).I'm using 1.13 to pull a
> USB-based recovery image, but there's an error in the
> backup/NETFS/default/50_make_backup.sh script that doesn't mount the USB
> device after the mkrecovery step, so subsequent tar fails on write to
> the non-existent mountpoint. I fixed that, but on recovery it fails to
> mount the necessary directories on the restore drive as well, so "rear
> recover" quickly bombs out. Is anyone having any success actually using
> ReaR on CentOS 6.x? - csawyer

It intentionally doesn't deal with drives the kernel has marked as
removable. I had trouble with that with the main drives on a SAS
hotswap backplane in an earlier version but I think that is fixed now.

I'd recommend asking how to override this on the ReaR mail list.
While the code seems usable (and yes, I have succeeded in using it on
Centos 6x.), the documentation either doesn't exist yet or is very out
of date. But, the authors are very responsive and it would be good
to let them know about any bugs or usability problems. The mail list
is still at sourceforge although the code has been moved to github and
there is talk of moving the list elsewhere.

--
Les Mikesell
lesmikesell@gmail.com
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 06-19-2012, 05:03 PM
Cal Sawyer
 
Default Best way to duplicate a live Centos 5 server?

Subject: Re: [CentOS] Best way to duplicate a live Centos 5 server?
To: CentOS mailing list <centos@centos.org>
On Mon, Jun 18, 2012 at 11:21 AM,
Cal Sawyer <cal-s@blue-bolt.com> wrote:
>> >
>> > ReaR has suddenly become very interesting to me, probably explaining why
>> > it utterly fails to work properly (for me).I'm using 1.13 to pull a
>> > USB-based recovery image, but there's an error in the
>> > backup/NETFS/default/50_make_backup.sh script that doesn't mount the USB
>> > device after the mkrecovery step, so subsequent tar fails on write to
>> > the non-existent mountpoint. I fixed that, but on recovery it fails to
>> > mount the necessary directories on the restore drive as well, so "rear
>> > recover" quickly bombs out. Is anyone having any success actually using
>> > ReaR on CentOS 6.x? - csawyer
> It intentionally doesn't deal with drives the kernel has marked as
> removable. I had trouble with that with the main drives on a SAS
> hotswap backplane in an earlier version but I think that is fixed now.
>
> I'd recommend asking how to override this on the ReaR mail list.
> While the code seems usable (and yes, I have succeeded in using it on
> Centos 6x.), the documentation either doesn't exist yet or is very out
> of date. But, the authors are very responsive and it would be good
> to let them know about any bugs or usability problems. The mail list
> is still at sourceforge although the code has been moved to github and
> there is talk of moving the list elsewhere.
>
> -- Les Mikesell lesmikesell@gmail.com

ReaR hasn't posed any insurmountable problems with USB removable media
but i can see SATA/SAS needing some massaging in the device detection dep't.

Yes, i've gotten myself on the ReaR mailing list now.

You're right - documentation is pretty dire. Guess i'm not alone in
hating doing it.

USB backup is broken due to the order in which path variables get set -
sure is lot of fun trawling through the scripts to find out what gets
set when. Hope the ReaR maintainers are interested in this and haven't
gotten themselves mired in tape
archive integration - i would have thought USB backup was the winner in
terms of getting broad acceptance as a bare-metal DR solution.

However, when it works - wow. Just restored an HP dl360 w/HWRAID to a
Presario desktop machine and it lives! No network, but that's small
beans compared to the larger win.

- csawyer
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 06-19-2012, 05:44 PM
Les Mikesell
 
Default Best way to duplicate a live Centos 5 server?

On Tue, Jun 19, 2012 at 12:03 PM, Cal Sawyer <cal-s@blue-bolt.com> wrote:
>
> You're right - documentation is pretty dire. *Guess i'm not alone in
> hating doing it.

Yes, I really, really wish the stuff they are doing was documented,
somewhere, anywhere. Not just how to use the program itself which is
supposed to 'just work' unattended once you set it up, but the black
magic of how they detect and reproduce all of the hardware, lvm, raid,
filesystem, etc. across different distributions and versions.

> USB backup is broken due to the order in which path variables get set -
> sure is lot of fun trawling through the scripts to find out what gets
> set when. *Hope the ReaR maintainers are interested in this and haven't
> gotten themselves mired in tape
> archive integration - i would have thought USB backup was the winner in
> terms of getting broad acceptance as a bare-metal DR solution.

USB is sort of 'hands-on' for something that should be unattended, and
adds a lot of unpredictable messiness in drive detection, boot order,
etc. All you really have to do is export some NFS space and point
ReaR to it. At least that is the easy way to get started. If you
have another Linux box, just plug your USB drive in there and access
it over NFS... problem solved.

Clonezilla-live plays in this space too, but it doesn't do raid or
multiple disks at once, and you have to shut down to take the image.

My 'ideal' system would be to have ReaR generate a directory of what
will be on the boot iso leaving that somewhere on the host without
actually making the image. Then use backuppc to back up the whole
host and its normal duplicate-pooling mechanism will keep the extra
copies of the tools from taking extra space. Then when/if you need a
bare-metal restore, you would first grab the directory of the iso
contents, burn a boot CD, let that reconstruct the filesystem, then
tell backuppc to restore to it. That way would be completely
automatic and always be up to date, with the advantage of backuppc's
efficient storage and easy online access to individual files and
directories. If you don't mind wasting a small amount of space for
the isos, I think that approach would already work if you tell ReaR to
just make the boot image and to wait for an external program to do the
restore after the filesystem has been rebuilt.

> However, when it works - wow. *Just restored an HP dl360 w/HWRAID to a
> Presario desktop machine and it lives! *No network, but that's small
> beans compared to the larger win.

Yes, I've even modified the filesystem layout file to go from a
software RAID to a non-RAID, and to change partition sizes during the
restores. If it was documented, that capability by itself would be
fantastic.

--
Les Mikesell
lesmikesell@gmail.com
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 07-08-2012, 10:48 PM
Micky
 
Default Best way to duplicate a live Centos 5 server?

The best and traditional way that has been there for decades is an rsync
and then reinstallation of boot-loader.
It works always if you know how it's done.

If you need detailed instructions, I can send you that!




On Tue, Jun 19, 2012 at 10:44 AM, Les Mikesell <lesmikesell@gmail.com>wrote:

> On Tue, Jun 19, 2012 at 12:03 PM, Cal Sawyer <cal-s@blue-bolt.com> wrote:
> >
> > You're right - documentation is pretty dire. Guess i'm not alone in
> > hating doing it.
>
> Yes, I really, really wish the stuff they are doing was documented,
> somewhere, anywhere. Not just how to use the program itself which is
> supposed to 'just work' unattended once you set it up, but the black
> magic of how they detect and reproduce all of the hardware, lvm, raid,
> filesystem, etc. across different distributions and versions.
>
> > USB backup is broken due to the order in which path variables get set -
> > sure is lot of fun trawling through the scripts to find out what gets
> > set when. Hope the ReaR maintainers are interested in this and haven't
> > gotten themselves mired in tape
> > archive integration - i would have thought USB backup was the winner in
> > terms of getting broad acceptance as a bare-metal DR solution.
>
> USB is sort of 'hands-on' for something that should be unattended, and
> adds a lot of unpredictable messiness in drive detection, boot order,
> etc. All you really have to do is export some NFS space and point
> ReaR to it. At least that is the easy way to get started. If you
> have another Linux box, just plug your USB drive in there and access
> it over NFS... problem solved.
>
> Clonezilla-live plays in this space too, but it doesn't do raid or
> multiple disks at once, and you have to shut down to take the image.
>
> My 'ideal' system would be to have ReaR generate a directory of what
> will be on the boot iso leaving that somewhere on the host without
> actually making the image. Then use backuppc to back up the whole
> host and its normal duplicate-pooling mechanism will keep the extra
> copies of the tools from taking extra space. Then when/if you need a
> bare-metal restore, you would first grab the directory of the iso
> contents, burn a boot CD, let that reconstruct the filesystem, then
> tell backuppc to restore to it. That way would be completely
> automatic and always be up to date, with the advantage of backuppc's
> efficient storage and easy online access to individual files and
> directories. If you don't mind wasting a small amount of space for
> the isos, I think that approach would already work if you tell ReaR to
> just make the boot image and to wait for an external program to do the
> restore after the filesystem has been rebuilt.
>
> > However, when it works - wow. Just restored an HP dl360 w/HWRAID to a
> > Presario desktop machine and it lives! No network, but that's small
> > beans compared to the larger win.
>
> Yes, I've even modified the filesystem layout file to go from a
> software RAID to a non-RAID, and to change partition sizes during the
> restores. If it was documented, that capability by itself would be
> fantastic.
>
> --
> Les Mikesell
> lesmikesell@gmail.com
> _______________________________________________
> CentOS mailing list
> CentOS@centos.org
> http://lists.centos.org/mailman/listinfo/centos
>
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 07-09-2012, 01:57 AM
Phil Savoie
 
Default Best way to duplicate a live Centos 5 server?

On 07/08/2012 06:48 PM, Micky wrote:
> The best and traditional way that has been there for decades is an rsync
> and then reinstallation of boot-loader.
> It works always if you know how it's done.
>
> If you need detailed instructions, I can send you that!

Yes, please! Could you either post here to the list, or to me personally?

Thank you,

Phil
--
Carpe Aptenodytes! (Seize the Penguins!)
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 07-09-2012, 02:14 AM
Joseph Spenner
 
Default Best way to duplicate a live Centos 5 server?

On Jul 8, 2012, at 6:57 PM, Phil Savoie <psavoie1783@rogers.com> wrote:

> On 07/08/2012 06:48 PM, Micky wrote:
>> The best and traditional way that has been there for decades is an rsync
>> and then reinstallation of boot-loader.
>> It works always if you know how it's done.
>>
>> If you need detailed instructions, I can send you that!
>
> Yes, please! Could you either post here to the list, or to me personally?
>
> Thank you,
>
> Phil
> --
>

What is running on the server? You might be able to get away with a dd, to build a duplicate disk. This disk can be directly attached or on another server tunneled through ssh.
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 07-09-2012, 02:30 AM
John R Pierce
 
Default Best way to duplicate a live Centos 5 server?

On 07/08/12 7:14 PM, Joseph Spenner wrote:
> What is running on the server? You might be able to get away with a dd, to build a duplicate disk. This disk can be directly attached or on another server tunneled through ssh.

or setup a drbd replica, wait for it to replicate, then stop the
replication.



--
john r pierce N 37, W 122
santa cruz ca mid-left coast

_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 07-09-2012, 03:20 AM
Phil Savoie
 
Default Best way to duplicate a live Centos 5 server?

On 07/08/2012 10:14 PM, Joseph Spenner wrote:
>
> On Jul 8, 2012, at 6:57 PM, Phil Savoie<psavoie1783@rogers.com> wrote:
>
>> On 07/08/2012 06:48 PM, Micky wrote:
>>> The best and traditional way that has been there for decades is an rsync
>>> and then reinstallation of boot-loader.
>>> It works always if you know how it's done.
>>>
>>> If you need detailed instructions, I can send you that!
>>
>> Yes, please! Could you either post here to the list, or to me personally?
>>
>> Thank you,
>>
>> Phil
>> --
>>
>
> What is running on the server? You might be able to get away with a dd, to build a duplicate disk. This disk can be directly attached or on another server tunneled through ssh.
>

Centos 5.8 and Centos 6.2 servers. A duplicate disk is not what I am
after as I cannot always replace with exact drives, i.e., same make,
model, size, etc.

But thank you anyway...

Phil

_______________________________________
> CentOS mailing list
> CentOS@centos.org
> http://lists.centos.org/mailman/listinfo/centos
>

Cen

--
Carpe Aptenodytes! (Seize the Penguins!)
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 07-09-2012, 04:06 AM
John R Pierce
 
Default Best way to duplicate a live Centos 5 server?

On 07/08/12 8:20 PM, Phil Savoie wrote:
> Centos 5.8 and Centos 6.2 servers. A duplicate disk is not what I am
> after as I cannot always replace with exact drives, i.e., same make,
> model, size, etc.

note that there's a lot of things where file by file, or even sector by
sector, duplicates are NOT valid if made while the system is online.

for instance, relational databases such as PostgreSQL, Oracle, you can't
just copy their files while the database server is running, as they rely
on writes being made in a specific order.





--
john r pierce N 37, W 122
santa cruz ca mid-left coast

_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 
Old 07-09-2012, 05:34 AM
Emmanuel Noobadmin
 
Default Best way to duplicate a live Centos 5 server?

On 7/9/12, Micky <mickylmartin@gmail.com> wrote:
> The best and traditional way that has been there for decades is an rsync
> and then reinstallation of boot-loader.
> It works always if you know how it's done.

The problem I found with rsync is that it is very slow when there are
a lot of small files. Any idea how this can be improved on or is that
a fundamental limit?
_______________________________________________
CentOS mailing list
CentOS@centos.org
http://lists.centos.org/mailman/listinfo/centos
 

Thread Tools




All times are GMT. The time now is 06:46 PM.

VBulletin, Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO ©2007, Crawlability, Inc.
Copyright 2007 - 2008, www.linux-archive.org