Hello,
If you are pinging subnet broadcast address, then it is expected.
Ping utility treats ICMP response with _same_ SEQ _and_ same or _different_ src.ip as duplicates.
Example:
- subnet 192.168.101.0/25
- subnet broadcast ip 192.168.101.127
- SRX interface ip 192.168.101.1
- when pinging 192.168.101.127, you receive 3 replies:
a) 1st from 192.168.101.2
b) 2nd from 192.168.101.3 with _SAME_ SEQ - this will be marked as DUP!
c) 3rd from 192.168.101.100 with _SAME_ SEQ - this will be also marked as DUP!
HTH
Rgds
Alex