I have two commands as listed below. 
 
I thought nsswitch should define the sequene to find a object. But, why ns-switch here is empty?
Then The source order here seems like similar to what nsswitch is supposed to do. Source Order and ns-switch, what are differences?
 
 
 
clus::vserver services name-service*> vserver show -vserver vserver1 -fields ns-switch
vserver ns-switch
--------- ---------
vserver1 -
clus::vserver services name-service*> vserver services name-service ns-switch show -vserver vserver1
                              Source
Vserver Database Order
--------------- ------------ ---------
vserver1 hosts files, 
                         dns
vserver1 group files, 
                         ldap
vserver1 passwd files,
                            ldap
vserver1 netgroup files
vserver1 namemap files
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