I have domain that is hosted by me. The DNS provider is dreamhost. I updated the IP address of the www.domain.com to x.x.x.200 from x.x.x.198, dnscheck show that changes have propagated correctly, but ping returns old IP back ? What could be the issue ?
A few considerations:
The TTL for the DNS zone (or individual A record) stipulates how long clients will cache the result.
If there are secondary DNS servers then the updated zone may not have been transferred yet. Test all name servers listed with WHOIS registrar record for the domain.
If you try pinging from a different workstation which has not recently exchanged with the specified hostname you will likely receive the updated IP (unless the secondary servers haven't been updated).