What happens on reboot/restart of images?

[alanwilliamson]

Morning one and all. First of all, let me say how pleased i am to see a real competitor to Amazon pop up on the radar.

We are a long term customer of Amazon, both with their S3 and EC2 services. Their S3 we cannot complain about in the slightest. It works, it works fast, and flexibility is good. It could do with a lot more, but isn't that always the way.

However, the same cannot be said of their EC2 service and it this I hope FlexiScale can fill in the miss gaps.

The biggest annoyance's with EC2 is the management surrounding restarting and rebooting.

The first one is the allocation of the IP address. Something as simple as that causes a lot of administration issues resorting to a DynDNS setup to simply get around the fact they can't allocate an IP address to be sticky. I believe this is a problem FlexiScale has already solved. Correct me if i am wrong.

Secondly and more importantly, is when the machine gets restarted (either through a software fault [rare i grante you], reboot, or even when Amazon have to restart a rack [it happens more than you think]) then all the data that was saved on the virtual disk is lost. You are back to square one.

As you can appreciate this is a complete pain for database driven applications. You find yourself getting into some elaborate setups with replication etc in the event of this happening.

What is FlexiScale doing on this front? Can you advise us what happens in this eventuality.

thank you,

alan

[tonylucas]

Morning one and all. First of all, let me say how pleased i am to see a real competitor to Amazon pop up on the radar.


Hi Alan, we're pleased to see people discovering us as well :)


We are a long term customer of Amazon, both with their S3 and EC2 services. Their S3 we cannot complain about in the slightest. It works, it works fast, and flexibility is good. It could do with a lot more, but isn't that always the way.

However, the same cannot be said of their EC2 service and it this I hope FlexiScale can fill in the miss gaps.



This is very similar to our thinking as well :) We are working on possibilities in the future to rival S3 as well however (as will be explained below) we have come at this from a hosting angle first.



The biggest annoyance's with EC2 is the management surrounding restarting and rebooting.

The first one is the allocation of the IP address. Something as simple as that causes a lot of administration issues resorting to a DynDNS setup to simply get around the fact they can't allocate an IP address to be sticky. I believe this is a problem FlexiScale has already solved. Correct me if i am wrong.



You are not wrong, each customer gets allocated a range of IP addresses that belong to them as long as they a customer (slight caveats may apply if you don't run a server for a long time, e.g weeks at a time, but if you don't you generally won't be bothered about your ip's changing anyway).



Secondly and more importantly, is when the machine gets restarted (either through a software fault [rare i grante you], reboot, or even when Amazon have to restart a rack [it happens more than you think]) then all the data that was saved on the virtual disk is lost. You are back to square one.

As you can appreciate this is a complete pain for database driven applications. You find yourself getting into some elaborate setups with replication etc in the event of this happening.

What is FlexiScale doing on this front? Can you advise us what happens in this eventuality.



All your data (unlike Amazon's) runs from a storage area network, so you can stop the server and start it up again without loosing any data at all. This was one of the key points when we built the platform, and we see it as a significant advantage over EC2. This also enables us to offer our SLA, as we can restart customers if physical nodes were to fail straight away, which Amazon can't.

We have built this platform having hosted websites large and small (and some very large) for the last 10 years, and accordingly have had to deal with just about every technical issue, and scalability problem you could imagine. We have used all this knowledge in building the platform.


thank you,

alan

Thank you for taking the time to investigate FlexiScale, we would love to know what you think when you've had chance to have a play with it.

Regards,

Tony Lucas
Chief Executive Officer
XCalibre Communications Ltd

[alanwilliamson]

Tony, I appreciate your personal reply. It's good to see the CEO getting down into the trenches and helping out with real customer problems.

We are also based in the UK (http://www.blog-city.com/) and at the moment we have a lot of data sitting on S3. We also have a number of images sitting on EC2 running instances of the blogging platform. Our mothership runs on a rack of DELL blade servers down in London.

Following on from your reply, i would like to understand a little more regarding the relationships between the running images and the backend storage.

Talk me through the logistics of say setting say a moderate DB server.

Would the MySQL InnoDB files reside on the same partition as the machine, or would that map back to a SAN which would be mounted as a partition?

Can images from the same client (aka me) all mount to the same SAN space?

So if I have a SAN account, when all my images come up (as and when I need them) can they all see the same files?

Many thanks, and I look forward to your answer.

[tonylucas]

Alan,

Thanks for the reply, I'm always happy to help.

If you were running a MySQL database the data itself would be stored on the SAN and mounted from there (of course if configured correctly most of the accesses would actually be cached in MySQL itself on the machine though).

If you were wanting multiple different servers to be able to access the same filesystem, we can offer this via NFS mounted storage, but this is not something we have completely rolled out yet (but we would welcome you to test it).

You could also of course run your own server and setup NFS on it as well if you wished to configure it directly yourself.

We can also do hybrid solutions where part of your service runs from FlexiScale, and part from co-located or dedicated servers with us, with no bandwidth fee's for internal traffic as well.

Hope this explains things, if not please let me know :)

Regards,

Tony.

[cdp]

Would the MySQL InnoDB files reside on the same partition as the machine, or would that map back to a SAN which would be mounted as a partition?



As far as a virtual server goes, it thinks it has a local disk. This disk even appears as /dev/hda in linux. The MySQL server will use it exactly as it would a physical disk. But this will map through to a virtual disk on the SAN. As a result we can boot the same virtual disk back up on another machine in the event of a hardware failure.

HTH