Re: official way to load aoe module?

[Etzion Bar-Noy]

RHCS is a good solution. I have just finished teaching it to one of Cisco's
development teams today. If you understand its abilities and limitations,
you can live happily with it.

OCFS2 solves the mount/disk management issues with HA clusters. However, it
does not solve application and access locking. For this there is a cluster.

Ez

On Mon, Aug 23, 2010 at 1:56 PM, Amos Shapira wrote:

> On 23 August 2010 14:47, Etzion Bar-Noy  wrote:
>
>> Adding LUNs does not require a reboot. Removing ones do. However, if you
>> let the cluster software manage all disk mount operations, as it should,
>> multiple-mounts will never happen, so no need for any special masking, but
>> only letting the cluster manage the mounts.
>>
>
> Indeed. Just today we had a long conference call with the hosting
> provider's SAN expert (they provide managed shared SAN service, very useful
> to cut costs) and that point was raised.
>
> We ended up doing what you describe - use a none-clustered file system and
> hope that RHCS does its job.
>
> Nope. I have been doing it for several years now, and I can quote the
>> procedure, if you like.
>> Download OCFS2 package for your kernel from here:
>>  http://oss.oracle.com/projects/ocfs2/files/RedHat/RHEL5/x86_64/1.4.7-1/ (I 
>> assumed it's x86_64 platform. Also - RHEL5)
>> Download OCFS2 tools from here:
>> http://
>> http://oss.oracle.com/projects/ocfs2-tools/files/RedHat/RHEL5/x86_64/1.4.4-1/(no
>>  need for the devel and debug packages)
>>
>> Install all three RPMs on all nodes.
>> Run, on each node, the command:
>> /etc/init.d/o2cb configure
>> Answer the questions.
>> Run on one node the GUI command (for first-timers) ocfs2console
>> Create a new clsuter, add all nodes with their names and IPs (if you have
>> multiple networks, select a non-busy one)
>> Press on "propagate cluster configuration" (or something similar, I don't
>> recall exactly), and you will have to insert the root password of each node
>> for "scp" command there.
>> Following that, your cluster is ready. Create a new partition, and mount
>> it. You will have to configure it to automatically mount via the /etc/fstab,
>> of course.
>>
>
> Thanks. Much appreciated.
> GUI and interactive tools are not an option, except maybe for first time
> learning-the-ropes. We configure everything automatically using puppet so
> we'll have to find a way to generate the files with that if we use it.
>
> Complexity. It increases the complexity of the RHCS configuration. It
>> requires RH cluster, even if you do not.
>>
>
> Does this mean that OCFS doesn't require RHCS? (not that it matters much
> now - we use RHCS for other reasons already and feel that a large part of
> the learning curve is behind us).
>
>  Cheers,
>
> --Amos
>
>
___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Amos Shapira]

On 23 August 2010 14:47, Etzion Bar-Noy  wrote:

> Adding LUNs does not require a reboot. Removing ones do. However, if you
> let the cluster software manage all disk mount operations, as it should,
> multiple-mounts will never happen, so no need for any special masking, but
> only letting the cluster manage the mounts.
>

Indeed. Just today we had a long conference call with the hosting provider's
SAN expert (they provide managed shared SAN service, very useful to cut
costs) and that point was raised.

We ended up doing what you describe - use a none-clustered file system and
hope that RHCS does its job.

Nope. I have been doing it for several years now, and I can quote the
> procedure, if you like.
> Download OCFS2 package for your kernel from here:
>  http://oss.oracle.com/projects/ocfs2/files/RedHat/RHEL5/x86_64/1.4.7-1/ (I 
> assumed it's x86_64 platform. Also - RHEL5)
> Download OCFS2 tools from here:
> http://
> http://oss.oracle.com/projects/ocfs2-tools/files/RedHat/RHEL5/x86_64/1.4.4-1/(no
>  need for the devel and debug packages)
>
> Install all three RPMs on all nodes.
> Run, on each node, the command:
> /etc/init.d/o2cb configure
> Answer the questions.
> Run on one node the GUI command (for first-timers) ocfs2console
> Create a new clsuter, add all nodes with their names and IPs (if you have
> multiple networks, select a non-busy one)
> Press on "propagate cluster configuration" (or something similar, I don't
> recall exactly), and you will have to insert the root password of each node
> for "scp" command there.
> Following that, your cluster is ready. Create a new partition, and mount
> it. You will have to configure it to automatically mount via the /etc/fstab,
> of course.
>

Thanks. Much appreciated.
GUI and interactive tools are not an option, except maybe for first time
learning-the-ropes. We configure everything automatically using puppet so
we'll have to find a way to generate the files with that if we use it.

Complexity. It increases the complexity of the RHCS configuration. It
> requires RH cluster, even if you do not.
>

Does this mean that OCFS doesn't require RHCS? (not that it matters much now
- we use RHCS for other reasons already and feel that a large part of the
learning curve is behind us).

Cheers,

--Amos
___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Etzion Bar-Noy]

Again, inline.

On Mon, Aug 23, 2010 at 2:46 AM, Amos Shapira wrote:

> On 23 August 2010 04:42, Etzion Bar-Noy  wrote:
> >
> > Inline
> >
> > On Sun, Aug 22, 2010 at 4:41 PM, Amos Shapira 
> wrote:
> >>
> >> Yes. But apart from hoping that RHCS does its job right, there is
> >> nothing preventing other guests from mounting the same partition in
> >> parallel.
> >>
> > Of course there is - LUN masking. Its purpose is exactly this. You expose
> the LUN *only* to the nodes which require direct access to it.
>
> The issue is that we want all our internal servers to be able to mount
> any of LUN's, as the "shards" of the multi-FS-multi-sqlite migrate
> among them.
> There is no way to dynamically mask and unmask LUN's, as it is now
> adding a new LUN requires a server reboot.
>

Adding LUNs does not require a reboot. Removing ones do. However, if you let
the cluster software manage all disk mount operations, as it should,
multiple-mounts will never happen, so no need for any special masking, but
only letting the cluster manage the mounts.

>
> >> That's why we looked at cluster-aware file systems in form of GFS but
> >> decided the performance hit is too great to go with it. A brief look
> >> at OCFS installation steps gave an impression that it isn't trivial or
> >> well supported on CentOS 5.
> >
> > Incorrect impression. Less than 5 minutes work, being extra slow, with
> coffee included. Simple enough?
>
> Thanks for the info. Do you have a good pointer to follow?
>
Nope. I have been doing it for several years now, and I can quote the
procedure, if you like.
Download OCFS2 package for your kernel from here:
 http://oss.oracle.com/projects/ocfs2/files/RedHat/RHEL5/x86_64/1.4.7-1/  (I
assumed it's x86_64 platform. Also - RHEL5)
Download OCFS2 tools from here:
http://
http://oss.oracle.com/projects/ocfs2-tools/files/RedHat/RHEL5/x86_64/1.4.4-1/(no
need for the devel and debug packages)

Install all three RPMs on all nodes.
Run, on each node, the command:
/etc/init.d/o2cb configure
Answer the questions.
Run on one node the GUI command (for first-timers) ocfs2console
Create a new clsuter, add all nodes with their names and IPs (if you have
multiple networks, select a non-busy one)
Press on "propagate cluster configuration" (or something similar, I don't
recall exactly), and you will have to insert the root password of each node
for "scp" command there.
Following that, your cluster is ready. Create a new partition, and mount it.
You will have to configure it to automatically mount via the /etc/fstab, of
course.

Have you compared OCFS performance to GFS and ext3?
>

Nope. I never bothered. I avoid GFS, as said, as much as possible, due to
its complexity, and I avoid clustered FS unless I must, so ext3 is not an
option then...

>
> >> It is. As was pointed out earlier in this thread - a large part of the
> >> "file system" is about how the file system module "caches" information
> >> in memory and synchronises it on the disk. If it's not a cluster-aware
> >> file system then parallel mounting is equivalent to opening the LV or
> >> device by an application and randomly starting to write data on it.
> >
> > True. But cluster-aware FS should be considered carefully. For some
> purposes, they ease management. For some others, they complicate it.
> > GFS has always been misunderstood by me. It has little benefits, and
> major drawbacks. Can't see any reason to use it, from the existing variety
> of clustered FS around.
>
> What drawbacks and compared to what? We've noticed the performance
> problem when we tried it. What are other *practical* alternatives?
> GFS comes built-in and supported in RHEL/CentOS and the RHCS, that's
> why it was the almost "natural choice" in our mind.
>
> Complexity. It increases the complexity of the RHCS configuration. It
requires RH cluster, even if you do not. It uses the cluster fencing
methods, which is somewhat good, but somewhat bad. I can't exactly point
there. Its implementation is somewhat ugly and over-complex to my liking.

Ez

Thanks,
>
> --Amos
>
___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Amos Shapira]

On 23 August 2010 04:42, Etzion Bar-Noy  wrote:
>
> Inline
>
> On Sun, Aug 22, 2010 at 4:41 PM, Amos Shapira  wrote:
>>
>> Yes. But apart from hoping that RHCS does its job right, there is
>> nothing preventing other guests from mounting the same partition in
>> parallel.
>>
> Of course there is - LUN masking. Its purpose is exactly this. You expose the 
> LUN *only* to the nodes which require direct access to it.

The issue is that we want all our internal servers to be able to mount
any of LUN's, as the "shards" of the multi-FS-multi-sqlite migrate
among them.
There is no way to dynamically mask and unmask LUN's, as it is now
adding a new LUN requires a server reboot.

>> That's why we looked at cluster-aware file systems in form of GFS but
>> decided the performance hit is too great to go with it. A brief look
>> at OCFS installation steps gave an impression that it isn't trivial or
>> well supported on CentOS 5.
>
> Incorrect impression. Less than 5 minutes work, being extra slow, with coffee 
> included. Simple enough?

Thanks for the info. Do you have a good pointer to follow?
Have you compared OCFS performance to GFS and ext3?

>> It is. As was pointed out earlier in this thread - a large part of the
>> "file system" is about how the file system module "caches" information
>> in memory and synchronises it on the disk. If it's not a cluster-aware
>> file system then parallel mounting is equivalent to opening the LV or
>> device by an application and randomly starting to write data on it.
>
> True. But cluster-aware FS should be considered carefully. For some purposes, 
> they ease management. For some others, they complicate it.
> GFS has always been misunderstood by me. It has little benefits, and major 
> drawbacks. Can't see any reason to use it, from the existing variety of 
> clustered FS around.

What drawbacks and compared to what? We've noticed the performance
problem when we tried it. What are other *practical* alternatives?
GFS comes built-in and supported in RHEL/CentOS and the RHCS, that's
why it was the almost "natural choice" in our mind.

Thanks,

--Amos

___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Etzion Bar-Noy]

Inline

On Sun, Aug 22, 2010 at 4:41 PM, Amos Shapira wrote:

> On 22 August 2010 23:22, Oleg Goldshmidt  wrote:
> >
> > On Sun, Aug 22, 2010 at 2:25 PM, Amos Shapira 
> wrote:
> >
> > > We are a little concerned about the situation of two guests mounting
> > > the ext3 and starting to manipulate the sqlite files on it in
> > > parallel.
> >
> > I think you should be *very* concerned about the situation where 2
> > guests mount an ext3 partition and start to manipulate files
> > *sequentially*. It looks like you *are* concerned (rightly), since you
> > wrote that only one client *mounts* the partition at a time.
>
> Yes. But apart from hoping that RHCS does its job right, there is
> nothing preventing other guests from mounting the same partition in
> parallel.
>
> Of course there is - LUN masking. Its purpose is exactly this. You expose
the LUN *only* to the nodes which require direct access to it.

> >
> > > Another option was to allow all guests to mount the file
> > > system read/write but carefully configure each guest to "own"
> > > different files or directories of sqlite files on the FS.
> >
> > What if one starts, e.g., creating files or appending content to
> > existing files (and allocating new blocks, etc., in the process)? The
> > other clients won't be aware of it.
>
> That's why we looked at cluster-aware file systems in form of GFS but
> decided the performance hit is too great to go with it. A brief look
> at OCFS installation steps gave an impression that it isn't trivial or
> well supported on CentOS 5.
>
Incorrect impression. Less than 5 minutes work, being extra slow, with
coffee included. Simple enough?

>
> >
> > I admit I have not thought long and hard about it, but it sounds
> > dangerous to me.
>
> It is. As was pointed out earlier in this thread - a large part of the
> "file system" is about how the file system module "caches" information
> in memory and synchronises it on the disk. If it's not a cluster-aware
> file system then parallel mounting is equivalent to opening the LV or
> device by an application and randomly starting to write data on it.
>
True. But cluster-aware FS should be considered carefully. For some
purposes, they ease management. For some others, they complicate it.
GFS has always been misunderstood by me. It has little benefits, and major
drawbacks. Can't see any reason to use it, from the existing variety of
clustered FS around.

Ez


>
> Cheers,
>
> --Amos
>
___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Amos Shapira]

On 22 August 2010 23:22, Oleg Goldshmidt  wrote:
>
> On Sun, Aug 22, 2010 at 2:25 PM, Amos Shapira  wrote:
>
> > We are a little concerned about the situation of two guests mounting
> > the ext3 and starting to manipulate the sqlite files on it in
> > parallel.
>
> I think you should be *very* concerned about the situation where 2
> guests mount an ext3 partition and start to manipulate files
> *sequentially*. It looks like you *are* concerned (rightly), since you
> wrote that only one client *mounts* the partition at a time.

Yes. But apart from hoping that RHCS does its job right, there is
nothing preventing other guests from mounting the same partition in
parallel.

>
> > Another option was to allow all guests to mount the file
> > system read/write but carefully configure each guest to "own"
> > different files or directories of sqlite files on the FS.
>
> What if one starts, e.g., creating files or appending content to
> existing files (and allocating new blocks, etc., in the process)? The
> other clients won't be aware of it.

That's why we looked at cluster-aware file systems in form of GFS but
decided the performance hit is too great to go with it. A brief look
at OCFS installation steps gave an impression that it isn't trivial or
well supported on CentOS 5.

>
> I admit I have not thought long and hard about it, but it sounds
> dangerous to me.

It is. As was pointed out earlier in this thread - a large part of the
"file system" is about how the file system module "caches" information
in memory and synchronises it on the disk. If it's not a cluster-aware
file system then parallel mounting is equivalent to opening the LV or
device by an application and randomly starting to write data on it.

Cheers,

--Amos

___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Etzion Bar-Noy]

Because it is.
Not in a way you will suffer physical damage. Your legs will be fine, and so
will be your hands.

Your data, on the other hand, will probably be very unhealthy...

Anyhow, RHCS, as a clustering infrastructure, should allow you to solve this
problem with minimal chance of human error.

Ez

On Sun, Aug 22, 2010 at 4:22 PM, Oleg Goldshmidt  wrote:

> On Sun, Aug 22, 2010 at 2:25 PM, Amos Shapira 
> wrote:
>
> > We are a little concerned about the situation of two guests mounting
> > the ext3 and starting to manipulate the sqlite files on it in
> > parallel.
>
> I think you should be *very* concerned about the situation where 2
> guests mount an ext3 partition and start to manipulate files
> *sequentially*. It looks like you *are* concerned (rightly), since you
> wrote that only one client *mounts* the partition at a time.
>
> > Another option was to allow all guests to mount the file
> > system read/write but carefully configure each guest to "own"
> > different files or directories of sqlite files on the FS.
>
> What if one starts, e.g., creating files or appending content to
> existing files (and allocating new blocks, etc., in the process)? The
> other clients won't be aware of it.
>
> I admit I have not thought long and hard about it, but it sounds
> dangerous to me.
>
> --
> Oleg Goldshmidt | o...@goldshmidt.org
>
___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Dima (Dan) Yasny]

Thinking about it, in this case there doesn't seem to be any gain in using
AoE or iSCSI over NFS. NFS is far from being perfect, but it takes care of
the shared FS, and since the network spped is the bottleneck here...

(reposted to all, my apologies)
On Sun, Aug 22, 2010 at 3:22 PM, Oleg Goldshmidt  wrote:

> On Sun, Aug 22, 2010 at 2:25 PM, Amos Shapira 
> wrote:
>
> > We are a little concerned about the situation of two guests mounting
> > the ext3 and starting to manipulate the sqlite files on it in
> > parallel.
>
> I think you should be *very* concerned about the situation where 2
> guests mount an ext3 partition and start to manipulate files
> *sequentially*. It looks like you *are* concerned (rightly), since you
> wrote that only one client *mounts* the partition at a time.
>
> > Another option was to allow all guests to mount the file
> > system read/write but carefully configure each guest to "own"
> > different files or directories of sqlite files on the FS.
>
> What if one starts, e.g., creating files or appending content to
> existing files (and allocating new blocks, etc., in the process)? The
> other clients won't be aware of it.
>
> I admit I have not thought long and hard about it, but it sounds
> dangerous to me.
>
> --
> Oleg Goldshmidt | o...@goldshmidt.org
>
> ___
> Linux-il mailing list
> Linux-il@cs.huji.ac.il
> http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
>
___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Oleg Goldshmidt]

On Sun, Aug 22, 2010 at 2:25 PM, Amos Shapira  wrote:

> We are a little concerned about the situation of two guests mounting
> the ext3 and starting to manipulate the sqlite files on it in
> parallel.

I think you should be *very* concerned about the situation where 2
guests mount an ext3 partition and start to manipulate files
*sequentially*. It looks like you *are* concerned (rightly), since you
wrote that only one client *mounts* the partition at a time.

> Another option was to allow all guests to mount the file
> system read/write but carefully configure each guest to "own"
> different files or directories of sqlite files on the FS.

What if one starts, e.g., creating files or appending content to
existing files (and allocating new blocks, etc., in the process)? The
other clients won't be aware of it.

I admit I have not thought long and hard about it, but it sounds
dangerous to me.

-- 
Oleg Goldshmidt | o...@goldshmidt.org

___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Amos Shapira]

On 22 August 2010 15:27, Etzion Bar-Noy  wrote:
>
> I think OCFS2 is slightly better.
> Listen - if you don't need clustered filesystem, avoid it at any cost. 
> However, if you do need it, then A/P cluster is not enough.

We are a little concerned about the situation of two guests mounting
the ext3 and starting to manipulate the sqlite files on it in
parallel. Another option was to allow all guests to mount the file
system read/write but carefully configure each guest to "own"
different files or directories of sqlite files on the FS.

Otherwise, there is no reason for us to use a clustered file system.
We ended up carving separate LUN's and separate Clustered LVM LV's
(Logical Volumes) and mounting/unmounting them from the relevant
guests and the processes get migrated among them through RHCS.

Cheers,

--Amos

___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Ehud Karni]

On Sat, 21 Aug 2010 01:30:58 Lior Kaplan wrote:
>
> The RedHat way:
> http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/5/html/Deployment_Guide/s1-kernel-modules-persistant.html

I think this is the OLD RedHat way.

Look at snippet from /etc/rc.sysinit of CentOS 5.5:

# Load other user-defined modules
for file in /etc/sysconfig/modules/*.modules ; do
  [ -x $file ] && $file
done

# Load modules (for backward compatibility with VARs)
if [ -f /etc/rc.modules ]; then
/etc/rc.modules
fi

So, the new way is to have a /etc/sysconfig/modules/.modules file.

I think this is better because unrelated modules are not in the same
file (like xinetd.d/ vs xinetd.conf).

One of the advantage of this approach is the ability to have such a
file included in an RPM (e.g. for AoE).

Ehud.

--
 Ehud Karni   Tel: +972-3-7966-561  /"\
 Mivtach - Simon  Fax: +972-3-7976-561  \ /  ASCII Ribbon Campaign
 Insurance agencies   (USA) voice mail and   X   Against   HTML   Mail
 http://www.mvs.co.il  FAX:  1-815-5509341  / \
 GnuPG: 98EA398D Better Safe Than Sorry

___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Etzion Bar-Noy]

I think OCFS2 is slightly better.

Listen - if you don't need clustered filesystem, avoid it at any cost.
However, if you do need it, then A/P cluster is not enough.

Ez

On Sun, Aug 22, 2010 at 12:01 AM, Amos Shapira wrote:

> 2010/8/22 Etzion Bar-Noy 
>
> Indeed.
>> The easiest to implement, amongst the free clustered filesystems is OCFS2
>> by Oracle. Two or three RPMs, a short configuration phase, and you're fine.
>>
>
> How is its performance?
>
> GFS comes as part of RHEL/CentOS base, so nothing special needs to be done
> to work with it.
>
> We tested it on a Fiber-Channel  EMC SAN device, compared it to plain ext3
> and xfs (yes we know that GFS is the only clustered one) and found that the
> performance hit too high to ignore.
>
> We ended up going back to ext3 and making sure only one guest mounts the
> filesystem at a time (that's what we need for our application anyway).
>
> --Amos
>
>
___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Amos Shapira]

2010/8/22 Etzion Bar-Noy 

> Indeed.
> The easiest to implement, amongst the free clustered filesystems is OCFS2
> by Oracle. Two or three RPMs, a short configuration phase, and you're fine.
>

How is its performance?

GFS comes as part of RHEL/CentOS base, so nothing special needs to be done
to work with it.

We tested it on a Fiber-Channel  EMC SAN device, compared it to plain ext3
and xfs (yes we know that GFS is the only clustered one) and found that the
performance hit too high to ignore.

We ended up going back to ext3 and making sure only one guest mounts the
filesystem at a time (that's what we need for our application anyway).

--Amos
___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Etzion Bar-Noy]

Indeed.
The easiest to implement, amongst the free clustered filesystems is OCFS2 by
Oracle. Two or three RPMs, a short configuration phase, and you're fine.

Ez

On Sat, Aug 21, 2010 at 4:20 PM, Oleg Goldshmidt  wrote:

> Hetz Ben Hamo  writes:
>
> > I just wonder about one thing which I haven't found a solution (yet)
> > for it: I mounted the aoe on 2 machines and I see the shared
> > partition from the server. So far, so good.
> >
> > But any change that I do on any machine is not being seen on the
> > other one.
> >
> > Anyone knows anything about this?
>
> AFAIK, AoE is a block level thing. What filesystem are you using?
>
> Unless it is a "distributed" ("clustered", whatever) filesystem like
> AFS or GPFS you simply cannot do it. If you try this with extN or
> CIFS/samba or anything "normal" all you'll get is a bunch of corrupted
> files.
>
> A filesystem does not live on disk only, it is represented as a bunch
> of data structures in your computer's memory. You cannot mount a disk
> on two independent computers simultaneously and expect consistency,
> unless the filesystem supports it.
>
> --
> Oleg Goldshmidt | p...@goldshmidt.org
>
___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Oleg Goldshmidt]

Hetz Ben Hamo  writes:

> I just wonder about one thing which I haven't found a solution (yet)
> for it: I mounted the aoe on 2 machines and I see the shared
> partition from the server. So far, so good.
>
> But any change that I do on any machine is not being seen on the
> other one.
>
> Anyone knows anything about this?

AFAIK, AoE is a block level thing. What filesystem are you using? 

Unless it is a "distributed" ("clustered", whatever) filesystem like
AFS or GPFS you simply cannot do it. If you try this with extN or
CIFS/samba or anything "normal" all you'll get is a bunch of corrupted
files.

A filesystem does not live on disk only, it is represented as a bunch
of data structures in your computer's memory. You cannot mount a disk
on two independent computers simultaneously and expect consistency,
unless the filesystem supports it.

-- 
Oleg Goldshmidt | p...@goldshmidt.org

___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Hetz Ben Hamo]

Thanks for the info.
I just wonder about one thing which I haven't found a solution (yet) for it:
I mounted the aoe on 2 machines and I see the shared partition from the
server. So far, so good.
But any change that I do on any machine is not being seen on the other one.

Anyone knows anything about this?

Thanks,
Hetz

2010/8/21 Etzion Bar-Noy 

> Oops. Reply all is better.
>
> Insert into /etc/modprobe.conf the line:
> alias scsi_hostadapter2 aoe
>
> Rebuild your initrd using mkinitrd, and it will be available on startup.
>
> Ez
>
> On Sat, Aug 21, 2010 at 11:23 AM, Shlomi Fish  wrote:
>
>> On Saturday 21 August 2010 01:20:26 Hetz Ben Hamo wrote:
>> > Hi,
>> > I'm trying to write a small mini-guide about AoE. So far, so good..
>> >
>> > The problem I'm facing is simple: what is the official way to autoload a
>> > module such aoe in distributions like CentOS/RedHat? I can put a simple
>> > modprobe line in rc.local but that doesn't look like a clean way..
>> >
>>
>> Just for the record, for people wondering what "AoE" is:
>>
>> http://en.wikipedia.org/wiki/ATA_over_Ethernet
>>
>> (That's what seems most likely - it's also "Age of Empires" and other
>> things).
>>
>> Regards,
>>
>>Shlomi Fish
>>
>> --
>> -
>> Shlomi Fish   http://www.shlomifish.org/
>> Funny Anti-Terrorism Story - http://shlom.in/enemy
>>
>> God considered inflicting XSLT as the tenth plague of Egypt, but then
>> decided against it because he thought it would be too evil.
>>
>> Please reply to list if it's a mailing list post - http://shlom.in/reply.
>>
>> ___
>> Linux-il mailing list
>> Linux-il@cs.huji.ac.il
>> http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
>>
>
>
> ___
> Linux-il mailing list
> Linux-il@cs.huji.ac.il
> http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
>
>


-- 
my blog (hebrew): http://benhamo.org
Skype: heunique
MSN: hetz-b...@benhamo.org
___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Fwd: Re: official way to load aoe module?

[Shlomi Fish]

--  Forwarded Message  --

Subject: Re: official way to load aoe module?
Date: Saturday 21 August 2010, 12:21:37
From: "Etzion Bar-Noy" 
To: Shlomi Fish 

Insert into /etc/modprobe.conf the line:
alias scsi_hostadapter2 aoe

Rebuild your initrd using mkinitrd, and it will be available on startup.

Etzion

On Sat, Aug 21, 2010 at 11:23 AM, Shlomi Fish  wrote:

> On Saturday 21 August 2010 01:20:26 Hetz Ben Hamo wrote:
> > Hi,
> > I'm trying to write a small mini-guide about AoE. So far, so good..
> >
> > The problem I'm facing is simple: what is the official way to autoload a
> > module such aoe in distributions like CentOS/RedHat? I can put a simple
> > modprobe line in rc.local but that doesn't look like a clean way..
> >
>
> Just for the record, for people wondering what "AoE" is:
>
> http://en.wikipedia.org/wiki/ATA_over_Ethernet
>
> (That's what seems most likely - it's also "Age of Empires" and other
> things).
>
> Regards,
>
>Shlomi Fish
>
> --
> -
> Shlomi Fish   http://www.shlomifish.org/
> Funny Anti-Terrorism Story - http://shlom.in/enemy
>
> God considered inflicting XSLT as the tenth plague of Egypt, but then
> decided against it because he thought it would be too evil.
>
> Please reply to list if it's a mailing list post - http://shlom.in/reply .
>
> ___
> Linux-il mailing list
> Linux-il@cs.huji.ac.il
> http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
>

-
-- 
-
Shlomi Fish   http://www.shlomifish.org/
"The Human Hacking Field Guide" - http://shlom.in/hhfg

God considered inflicting XSLT as the tenth plague of Egypt, but then
decided against it because he thought it would be too evil.

Please reply to list if it's a mailing list post - http://shlom.in/reply .

___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Etzion Bar-Noy]

Oops. Reply all is better.

Insert into /etc/modprobe.conf the line:
alias scsi_hostadapter2 aoe

Rebuild your initrd using mkinitrd, and it will be available on startup.

Ez

On Sat, Aug 21, 2010 at 11:23 AM, Shlomi Fish  wrote:

> On Saturday 21 August 2010 01:20:26 Hetz Ben Hamo wrote:
> > Hi,
> > I'm trying to write a small mini-guide about AoE. So far, so good..
> >
> > The problem I'm facing is simple: what is the official way to autoload a
> > module such aoe in distributions like CentOS/RedHat? I can put a simple
> > modprobe line in rc.local but that doesn't look like a clean way..
> >
>
> Just for the record, for people wondering what "AoE" is:
>
> http://en.wikipedia.org/wiki/ATA_over_Ethernet
>
> (That's what seems most likely - it's also "Age of Empires" and other
> things).
>
> Regards,
>
>Shlomi Fish
>
> --
> -
> Shlomi Fish   http://www.shlomifish.org/
> Funny Anti-Terrorism Story - http://shlom.in/enemy
>
> God considered inflicting XSLT as the tenth plague of Egypt, but then
> decided against it because he thought it would be too evil.
>
> Please reply to list if it's a mailing list post - http://shlom.in/reply .
>
> ___
> Linux-il mailing list
> Linux-il@cs.huji.ac.il
> http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
>
___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Shlomi Fish]

On Saturday 21 August 2010 01:20:26 Hetz Ben Hamo wrote:
> Hi,
> I'm trying to write a small mini-guide about AoE. So far, so good..
> 
> The problem I'm facing is simple: what is the official way to autoload a
> module such aoe in distributions like CentOS/RedHat? I can put a simple
> modprobe line in rc.local but that doesn't look like a clean way..
> 

Just for the record, for people wondering what "AoE" is:

http://en.wikipedia.org/wiki/ATA_over_Ethernet

(That's what seems most likely - it's also "Age of Empires" and other things).

Regards,

Shlomi Fish

-- 
-
Shlomi Fish   http://www.shlomifish.org/
Funny Anti-Terrorism Story - http://shlom.in/enemy

God considered inflicting XSLT as the tenth plague of Egypt, but then
decided against it because he thought it would be too evil.

Please reply to list if it's a mailing list post - http://shlom.in/reply .

___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Hetz Ben Hamo]

Weird, they don't even create the file.

Thank you Lior.

Hetz

2010/8/21 Lior Kaplan 

> The RedHat way:
> http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/5/html/Deployment_Guide/s1-kernel-modules-persistant.html
>
> Kaplan
>
> 2010/8/21 Hetz Ben Hamo 
>
>> Hi,
>> I'm trying to write a small mini-guide about AoE. So far, so good..
>>
>> The problem I'm facing is simple: what is the official way to autoload a
>> module such aoe in distributions like CentOS/RedHat? I can put a simple
>> modprobe line in rc.local but that doesn't look like a clean way..
>>
>> Any suggestions?
>>
>> Thanks,
>> Hetz
>>
>> --
>> my blog (hebrew): http://benhamo.org
>> Skype: heunique
>> MSN: hetz-b...@benhamo.org
>>
>> ___
>> Linux-il mailing list
>> Linux-il@cs.huji.ac.il
>> http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
>>
>>
>

-- 
my blog (hebrew): http://benhamo.org
Skype: heunique
MSN: hetz-b...@benhamo.org
___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

Re: official way to load aoe module?

[Lior Kaplan]

The RedHat way:
http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/5/html/Deployment_Guide/s1-kernel-modules-persistant.html

Kaplan

2010/8/21 Hetz Ben Hamo 

> Hi,
> I'm trying to write a small mini-guide about AoE. So far, so good..
>
> The problem I'm facing is simple: what is the official way to autoload a
> module such aoe in distributions like CentOS/RedHat? I can put a simple
> modprobe line in rc.local but that doesn't look like a clean way..
>
> Any suggestions?
>
> Thanks,
> Hetz
>
> --
> my blog (hebrew): http://benhamo.org
> Skype: heunique
> MSN: hetz-b...@benhamo.org
>
> ___
> Linux-il mailing list
> Linux-il@cs.huji.ac.il
> http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
>
>
___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il

official way to load aoe module?

[Hetz Ben Hamo]

Hi,
I'm trying to write a small mini-guide about AoE. So far, so good..

The problem I'm facing is simple: what is the official way to autoload a
module such aoe in distributions like CentOS/RedHat? I can put a simple
modprobe line in rc.local but that doesn't look like a clean way..

Any suggestions?

Thanks,
Hetz

-- 
my blog (hebrew): http://benhamo.org
Skype: heunique
MSN: hetz-b...@benhamo.org
___
Linux-il mailing list
Linux-il@cs.huji.ac.il
http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il