How can sampling be enabled on inet interfaces?

Sampling is missing on some inet interfaces

There are two ways sampling can be enabled on an inet interface.

1) If sampling needs to be applied to all the traffic of an interface:
 

set interface <interface-name> unit <#no> family inet sampling <traffic-direction input/output>

eg:

 set interfaces xe-0/0/0 unit 10 family inet sampling input  [for input direction]
 set interfaces xe-0/0/0 unit 10 family inet sampling ouput  [for output direction]

2) If sampling needs to be enabled for the selected flow traffic, a firewall term can be used:
 

set firewall family inet filter <filter-name> term <term-name> then sample 
set interfaces <interface-name> unit <#no> family inet filter input <filter-name>  [for input direction]
set interfaces <interface-name> unit <#no> family inet filter input <filter-name> [for ouput direction]

eg:

set firewall family inet filter SAMPLE term STERM-IN from source-address 1.1.1.1 
set firewall family inet filter SAMPLE term STERM-IN from destination-address 2.2.2.2      
set firewall family inet filter SAMPLE term STERM-IN then sample               
set firewall family inet filter SAMPLE term STERM-OUT from source-address 2.2.2.2
set firewall family inet filter SAMPLE term STERM-OUT from destination-address 1.1.1.1    
set firewall family inet filter SAMPLE term STERM-OUT then sample              
set interfaces xe-0/0/0 unit 10 family inet filter input SAMPLE 
set interfaces xe-0/0/0 unit 10 family inet filter output SAMPLE