Changing default scheduler in hadoop

[Mahesh Khandewal]

Sir i am using Hadoop 1.1.2
I don't know where is the code residing of default scheduler?
I want to change the default scheduler to fair how can i do this??
And if i want to get back to default scheduler how can i do this?
I am struggling since 4 months to get help on Apache Hadoop??
I am new to this mailing list