Hi Kahina,
You can do this via the below command and check the bps on st0 interface ;
SRX> monitor interface traffic
SRX Seconds: 36 Time: 19:30:19
Interface Link Input bytes (bps) Output bytes (bps)
fe-0/0/4 Down 0 (0) 0 (0)
fe-0/0/5 Down 0 (0) 0 (0)
fe-0/0/6 Up 34980 (0) 24486 (0)
fe-0/0/7 Up 34980 (0) 24486 (0)
fxp2 Up 23400 31816850
gre Up 0 0
ipip Up 0 0
irb Up 0 0
lo0 Up 91318737 91318737
lsi Up 0 0
mtun Up 0 0
pimd Up 0 0
pime Up 0 0
pp0 Up 0 (0) 0 (0)
ppd0 Up 0 (0) 0 (0)
ppe0 Up 0 (0) 0 (0)
st0 Up 109980 (0) 162985 (0)
tap Up 0 0
vlan Up 0 (0) 0 (0)
Bytes=b, Clear=c, Delta=d, Packets=p, Quit=q or ESC, Rate=r, Up=^U, Down=^D
Thanks,
Shailesh
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