Question : Having issue in DNS  Different machins have same IP address ?

MY DHCP lease period is 1days and DNS scavenging for refresh interval is 1 days and non-refresh interval is 1days. Beside that we have not setup anything.
Do we need to enabled scvanging period ?  We have not done that

Answer : Having issue in DNS  Different machins have same IP address ?

I would go for 1 day on the Scavenging Period for everything but very big domains (5000+ clients).

2 days is better for the lease, really the longer it is the easier it is to keep things neat and tidy (provided you don't run out of IP Addresses).

Chris