Re: How scalable is Cfengine, and some other questions?

[Mark . Burgess]

Tobias, just in brief. I have not too much time today.
(Come to LISA2004 for more answers!! :))

On  9 Nov, Tobias Svensson wrote:
> Hi,
> 
> I'm looking in to Cfengine to see if it fits our solution. However, there 
> are a couple of questions I would like to have answers to.
> 
> 
> 1) Are there any companies preferebly in Europe that offers support on 
> Cfengine?

Yes, but it depends on what you are looking for.

> 2) How scalable is Cfengine? A solution that needs to update more then 
> 10.000 clients with a lot of data in each batch (100 MB over 128 Mbits/s 
> lines). Would Cfengine work here?

The largest I know of was planned at 11.000. I have not heard back from these.
But there are several with about 4000.

> 3) With 2) in mind, is there some way to coordinate many Cfengine 
> distribution hosts?

There are lots of models, pick one and go with it. Cfengine is flexible.
I can make suggestions here at a later date.

> 4) My idea is that 3) could be solved by connecting the Cfengine hosts to a 
> database that handles the coordination. What’s the best way to connect to a 
> DB from Cfengine  or would it be best to go through an own application when 
> connecting to a db?

Cfengine does not interface directly with any databases, but you can use modules
in script languages to interface.

> 5) To my understanding, Cfengine uses rsync for the distribution of data. 
> Rsync is pretty expensive when it comes to memory usage. With that in mind, 
> how many batches do you recommend to keep concurrently from a Cfengine PC 
> server (4 GB memory).
>

Cfengine does not use rsync. Its native copy command is less speed efficient,
but focusses on security and integrity and is cheap on memory.

> 6) Is it possible to use an updating scheme where all clients connect to a 
> socket on the Cfengine host and then, when the server decides the  update 
> should occur.

You make this sound hard. By design it is not possible to force any host
to do anything it doesn't want to, so centralized control is not an exact
science. However, in practice you can send hints to clients to update
immediately using cfrun. That is not exactly the same as you say, but it
is equivalent.


> 7) How stable is the Windows version of Cfengine? Does it work with Windows 
> XP? What parts are incompatible to the core version?

It works on Xp. I don't know what the core version means.

> 8) How is CRLF problems handled if I update a Windows XP host with files 
> from a Linux Cfengine host?

I think this is transparent, but I would have to check.

> 9) Can Cfengine handle Tivoli DUs (distributin units)?


I don't know what Tivoli DUs are. Cfengine doesn't have any connection
with proprietary products.


Mark