I have recently experienced some DNS problems and so decided to look into configuring an alternative or Secondary DNS for my domain. A secondary DNS server will copy the DNS settings from your primary DNS server on a regular basis, so there is no need to maintain two sets of data. If you use separate records, then browsers will have problems deciding which is up to date. There are several free services out there including Twisted for Life and Zone Edit. Other fee paying services you might consider are SecondaryDNS or EasyDNS.
Once you have signed up with your secondary DNS provider, you will need to submit a support ticket to your hosting provider (unless you have true root access) in order to modify your current DNS server’s configuration. Let's assume that your new nameserver is called ns1.alternativeDNS.com. On Westhost you will need to ask them to edit your BIND file (/var/named/db.yourdomain.com) and add a line similar to yourdomain.com. IN NS ns1.alternativeDNS.com. The trailing dot is important!. Your hosting provider may also have to add ns1.alternativeDNS.com to their nameserver to permit AXFR transfers of the information . If this does not work, try editiing /etc/named.conf.
Once this has been done, your secondary DNS provider will be able to mirror the details from your current provider. You can check that your secondary DNS provider has the correct information by retrieving the information from their nameserver. You need to type nslookup www.yourdomain.com ns1.alternativeDNS.com in Windows, or dig @ns1.alternativeDNS.com www.yourdomain.com in Linux.
The final step is to modify the nameserver entries with your registrar. Log in to your account with them and add this new nameserver to your existing list. This will take a while to propogate around the internet, so come back later and check that all your nameservers are listed when you use the command nslookup -type=NS yourdomain.com in Windows or dig -t NS yourdomain.com in Linux.
Check that everything is correct by going to DNSReport.com