Nz_migrate throws the error

Issue:
when I tried to migrate the date from source to target ,got the below error and looks like all syntax and everything correct,even though got the below error.

nz@<netezza_server_name>:nz@NPS_HOST:/export/home/nz> nz_migrate -shost NPS_HOST -thost NPS_HOST -sdb DBA_DB -tdb NPS_DB_OLD  -tableFile  /export/home/nz/NPS_DB_OLD_tbl.log  -suser admin -spassword  ****** -tuser admin -tpassword ****** -CreateTargetTable YES -TruncateTargetTable NO -format binary  -threads 4

-bash: !0: event not found

Solution:
just use single quote on the password character,it will  run without any issues.double  quote wont work.

nz_migrate -shost NPS_HOST -thost NPS_HOST -sdb DBA_DB -tdb NPS_DB_OLD  -tableFile  /export/home/nz/NPS_DB_OLD_tbl.log  -suser admin -spassword  '****** '-tuser admin -tpassword '******' -CreateTargetTable YES -TruncateTargetTable NO -format binary  -threads 4