Change providers now. Any DC that isn't actually around to fix problems after hours or on a weekend isn't someone that you can go with to actually provide a shared environment to actual customers. A cheap box from someone like that is fine if it is something personal that you don't care about downtime on, but not when you are providing service to others or have your own mission critical sites.
A hosting company, no matter who they are, is only as good as their upstream provider. This goes for resellers, leased servers, co-lo and direct purchases of bandwidth providers.
As far as your customers, being honest is going to go a long way in helping you keep them. Tell them what has happened and what you plan to do in the future to avoid this type of problem. Then make sure you follow that plan of action to prevent a repeat.
If your customers' websites have been down for a week, they should get their refund. I know I would demand one. You should issue a refund to those that ask for it before they issue a chargeback with their credit card company, then it would get really costly for you.
In order to avoid losing too many customers, you might want to email them and let them know that if they stick it out, you'll give them some kind of reward, like a couple of free months maybe.
my server was DoS attacked badly, and now is unpingable. My data centre (managed) is not helpfull at all.
Ive already handed out refunds and lost lots of money.
I have people complaining on messenger, via email its a disaster.
Due to it been the weekend the DC aren't there and they are going to have to re image the server.
What should I do? I feel so bad for all my customers.
Looks like you are looking for different possible solutions.
Another possible solution would be to contact another larger host or a company who deals with mergers and people who aquire other companies.
You may want to look into selling out your company if everyone is asking for a refund. You can sell the customers accounts to a larger company, and make enough money to pay the refunds...
Although unlikely, it is an option.
Well while, I have no experience with Managed.com in a hosting environment, I do know that we had sent several legal notices that have gone unanswered as well.
This seems to be a habit
Again, my experience with their response time, or lack thereof, is not in a hosting environment, but I think it surely relates. I mean if they do not reply to our attorneys, over an issue of copyright infringement, then it speaks volumes, IMO about them replying to anything, with any type of punctuallity.