DNS Changes-New Website

[Bankesy]

Hello

 

I am having difficulty understanding DNS and the records within following the implementation of a new school website, it used to be internally hosted now it is externally hosted.

 

However inside the school we still see the old site but outside everybody can see the new one following the DNS change request processed by Thurrock County Council.

 

So my best guess is we cannot see the new one internally due to some sort of DNS problem.

 

Where I have got to so far:

 

1.-On the DNS server I have found the forward lookup zone for testschool.county.sch.uk

2.-Inside here is a 'www' Host (A) entry which has our website address for a fully qualified domain name and the IP of our webserver

 

According to the hosting company I am required to create a CNAME Alias record for testschool.testcms.co.uk

 

However when I attempt this inside the forward lookup zone the fully qualified domain name box is greyed out and reads testschool.county.sch.uk and simply adds as a prefix whatever I type as the name for the record.

 

I try to use www and testschool.testcms.co.uk for the name and fully qualified domain name of the target host but get an error message which I assume is due to there being an a Host (A) record with the same name.

 

I did try deleting the www Host (A) record but this stopped other things from working.

 

Can anybody tell from that description what I might be doing wrong?

 

All help appreciated, thank you in advance.