how do web hosting companies give ssh and root to so many users.

[Kapil Thangavelu]

On 03/05/2011 09:42 AM, Abhishek Dixit wrote:
> On Sat, Mar 5, 2011 at 7:08 PM, Ahmed Kamal<kim0 at ubuntu.com>  wrote:
>>
>>
>> On 03/05/2011 03:24 PM, Abhishek Dixit wrote:
>>>
>>> So if some one has to host 100 million websites and if 10 million asks
>>> then the web hosting company has these 10 million IP addresses?
>>
>> Websites are different. Due to "Name Virtualhosting" you can host multiple
>> websites (thousands) on a single IP address. The web server knows how to
>> serve the correct one through http headers
>>
> Very correct.But I see people given root access in these situations
> also and other than websites people are given a lot of server access
> with dedicated IPs and SSH access so how do they acquire so many
> IPs.Are these web hosting companies responsible for the finishing of
> IPv4 addresses.

Another approach that would be conservative of the ipv4 address space, A 
custom ssh server implementation, and chroot + a grsecurity kernel. On 
ssh login dispatch the user to their web space in a chroot on machine x, 
ideally on cluster shared fs. grsecurity provides some facilities to 
secure chroots.

cheers,

Kapil