Re: [CentOS-virt] Introducing ConVirt 2.0

2010-03-07 Thread Pasi Kärkkäinen 
On Sun, Mar 07, 2010 at 02:54:53AM -0600, Christopher G. Stach II wrote:
> - "Pasi Kärkkäinen"  wrote:
> 
> > On Sat, Mar 06, 2010 at 09:04:20AM -0500, Kanwar Ranbir Sandhu wrote:
> > > Why would one use ConVirt instead of the management tools included in
> > > RHEL and/or CentOS?  What's the difference?
> > 
> > RHEL/CentOS doesn't provide web-based management.. or even easy 
> > multi-host / cluster management of virtualization nodes.
> > 
> > -- Pasi
> 
> Are there any *good* reasons? (Since I really hate commercials, I feel 
> compelled to present my contrarian viewpoint.) ConVirt addresses a pretty 
> small portion of the virtualization landscape, and it consists of only a few 
> significant parts:
> 
> 1. Do what other free and open tools already do.
> 2. Slap a web interface on it!
> 3. Spam lists.
> 4. Rope in suckers.
> 
> The suggestion that a web interface is a value add to an infrastructure issue 
> is at least insulting. You could attempt to slap a web interface on a fuel 
> injection system (or maybe at least give access to the magic a la 
> MegaSquirt), but a bunch of assholes are still going to blow something up. 
> It's not going to give any admin worth his or her salt a boner because it's 
> not readily scriptable and it amounts to candy for retards. Secondly, 
> everything else that it does is already there. If you can't do it, you 
> shouldn't be touching the machines.
> 
> The tool may or may not address some vanilla installations (if there ever was 
> one), but if you need something like that, you are probably better off with 
> EC2 or at least letting someone else handle it.
> 

You have some good points here. An user API is absolutely a requirement for 
system like this,
to let the powerusers/admins script things and create custom management scripts.

Web interface frontend should/could be using the same API!

-- Pasi

___
CentOS-virt mailing list
CentOS-virt@centos.org
http://lists.centos.org/mailman/listinfo/centos-virt

Re: [CentOS-virt] [fedora-virt] Thoughts on storage infrastructure for small scale HA virtual machine deployments

2010-03-07 Thread Dennis J. 
On 03/02/2010 04:51 AM, Ask Bjørn Hansen wrote:
>
> On Mar 1, 2010, at 18:56, Dennis J. wrote:
>
>> The question that bugs me is how I can get enough bandwidth between the
>> hosts and the storage to provide the VMs with reasonable I/O performance.
>> If all the 40 VMs start copying files at the same time that would mean that
>> the bandwidth share for each VM would be tiny.
>
> It really depends on the specific workloads.  In my experience it's generally 
> the number of IOs per second rather than the bandwidth that's the limiting 
> factor.
>
> We have a bunch of 4-disk boxes with md raid10 and we generally run out of 
> disk IO before we run out of memory (~24-48GB) or CPU (dual quad core 2.26GHz 
> or some such).

That's very similar to what we are experiencing. The primary Problem for me 
is how to deal with the bottleneck of a shared storage setup. The most 
simple setup is a 2-system criss-cross setup where the two hosts also serve 
as halves for a DRBD cluster. The advantage of this approach is that it's a 
cheap solution, that only a part of the storage-traffic has to go over the 
network between the machines and that the network only hast to handle the 
sorage-traffic of the VMs of those two machines.
The disadvantage of that approach is that you have to keep 50% of potential 
server capacity free in case of a failure of the twin node. That's quite a 
lot of wasted capacity.
To reduce that problem you can increase the number of hosts to let say for 
an example four which would reduce the spare capacity needed to 33% on each 
system but then you really need to separate the storage from the hosts an 
now you have a bottleneck on the storage end. Increase the number of hosts 
to 8 and you get even less wasted capacity but also increase the pressure 
on the storage bottleneck a lot.
Since I'm new to the whole SAN aspect I'm currently just looking at all the 
options that are out there and basically wonder how the big boys are 
handling this who have hundreds if not thousand of VMs running and need to 
be able to deal with physical failures too.
That is why I find the sheepdog project so interesting because it seems to 
address this particular problem in a way that would provide almost linear 
scalability without actually using a SAN at all (well, at least not in the 
traditional sense of the word).

Regards,
   Dennis
___
CentOS-virt mailing list
CentOS-virt@centos.org
http://lists.centos.org/mailman/listinfo/centos-virt

Re: [CentOS-virt] Introducing ConVirt 2.0

2010-03-07 Thread Grant McWilliams 
On Sun, Mar 7, 2010 at 12:54 AM, Christopher G. Stach II wrote:

> - "Pasi Kärkkäinen"  wrote:
> >
> > RHEL/CentOS doesn't provide web-based management.. or even easy
> > multi-host / cluster management of virtualization nodes.
> >
> > -- Pasi
>
> Are there any *good* reasons? (Since I really hate commercials, I feel
> compelled to present my contrarian viewpoint.) ConVirt addresses a pretty
> small portion of the virtualization landscape, and it consists of only a few
> significant parts:
>
> 1. Do what other free and open tools already do.
> 2. Slap a web interface on it!
> 3. Spam lists.
> 4. Rope in suckers.
>
> The suggestion that a web interface is a value add to an infrastructure
> issue is at least insulting. You could attempt to slap a web interface on a
> fuel injection system (or maybe at least give access to the magic a la
> MegaSquirt), but a bunch of assholes are still going to blow something up.
> It's not going to give any admin worth his or her salt a boner because it's
> not readily scriptable and it amounts to candy for retards. Secondly,
> everything else that it does is already there. If you can't do it, you
> shouldn't be touching the machines.
>
> The tool may or may not address some vanilla installations (if there ever
> was one), but if you need something like that, you are probably better off
> with EC2 or at least letting someone else handle it.
>
> --
> Christopher G. Stach II
> http://ldsys.net/~cgs/ 
>

As these tools become more mature I'd like to see some comparisons because I
too get a little tired of all the hype surrounding 20 tools that do exactly
the same thing. I played with Convirt quite a while ago but it either didn't
install right or didn't work right. Version 2.0 looks better. But then we
have Eucalyptus, Enomalism, Convirt, Orchestra, Xen Admin, DTC-Xen, Cloudmin
and I'd guess a whole bunch more. I wrote my own for classroom purposes that
reads a roster and lets me act on whole classes of machines. I didn't
release it because I think we have enough Xen guis. What we need to do is
combine resources and make one real GOOD one.

Grant McWilliams
___
CentOS-virt mailing list
CentOS-virt@centos.org
http://lists.centos.org/mailman/listinfo/centos-virt

Re: [CentOS-virt] Thoughts on storage infrastructure for small scale HA virtual machine deployments

2010-03-07 Thread Christopher G. Stach II 
- "Grant McWilliams"  wrote:

> I'm replacing my setup with
> three Intel SSDs in a RAID0 with either iSCSI or ATAoE. The RAID0 will
> be synced to a disk based storage as backup. We'll see pretty soon how
> many concurrent disk based operations this setup can handle.

I haven't benchmarked anything like that in a while. I'm not saying that RAID 0 
with 3 targets is going to be non-performant, but I would expect a parallel 
array to be better for random ops unless a classroom workload falls into 
sequential for some reason (software installation). Do you have any numbers 
testing this, or better, real world stats?

-- 
Christopher G. Stach II
http://ldsys.net/~cgs/
___
CentOS-virt mailing list
CentOS-virt@centos.org
http://lists.centos.org/mailman/listinfo/centos-virt

Re: [CentOS-virt] Introducing ConVirt 2.0

2010-03-07 Thread Christopher G. Stach II 
- "Pasi Kärkkäinen"  wrote:

> On Sat, Mar 06, 2010 at 09:04:20AM -0500, Kanwar Ranbir Sandhu wrote:
> > Why would one use ConVirt instead of the management tools included in
> > RHEL and/or CentOS?  What's the difference?
> 
> RHEL/CentOS doesn't provide web-based management.. or even easy 
> multi-host / cluster management of virtualization nodes.
> 
> -- Pasi

Are there any *good* reasons? (Since I really hate commercials, I feel 
compelled to present my contrarian viewpoint.) ConVirt addresses a pretty small 
portion of the virtualization landscape, and it consists of only a few 
significant parts:

1. Do what other free and open tools already do.
2. Slap a web interface on it!
3. Spam lists.
4. Rope in suckers.

The suggestion that a web interface is a value add to an infrastructure issue 
is at least insulting. You could attempt to slap a web interface on a fuel 
injection system (or maybe at least give access to the magic a la MegaSquirt), 
but a bunch of assholes are still going to blow something up. It's not going to 
give any admin worth his or her salt a boner because it's not readily 
scriptable and it amounts to candy for retards. Secondly, everything else that 
it does is already there. If you can't do it, you shouldn't be touching the 
machines.

The tool may or may not address some vanilla installations (if there ever was 
one), but if you need something like that, you are probably better off with EC2 
or at least letting someone else handle it.

-- 
Christopher G. Stach II
http://ldsys.net/~cgs/
___
CentOS-virt mailing list
CentOS-virt@centos.org
http://lists.centos.org/mailman/listinfo/centos-virt