I changed from an old, broken server to a new one and moved all sites (using ispcfg 3) to the new server.
everythign went smooth except for one domain.
this one domain is a co.za domain, registered via marcaria.com and using their DNS. I only provide the website content.
after this move I asked the owner to change his DNS to point to the new server.
the result is that now his A-records point to the old and the new server, giving you a 50% chance of landing on the right server.
here are two tests:
shows two IPs for the a-record and
shows several DNS issues.
I asked the client to chat with the co.za registry but they sent him to me, same goes for marcaria.com whose DNS servers he is using.
since I don't provide anything else than hosting for him, I am not sure how I can fix this and where this problem could originate on my server.