locale: Cannot set LC_CTYPE / LC_MESSAGES / LC_ALL

issue:

locale: Cannot set LC_CTYPE to default locale: No such file or directory
locale: Cannot set LC_MESSAGES to default locale: No such file or directory
locale: Cannot set LC_ALL to default locale: No such file or directory

fix:

root@CRIS-CAT:# locale
locale: Cannot set LC_CTYPE to default locale: No such file or directory
locale: Cannot set LC_MESSAGES to default locale: No such file or directory
locale: Cannot set LC_ALL to default locale: No such file or directory
LANG=en_US.UTF-8
LANGUAGE=
LC_CTYPE="en_US.UTF-8"
LC_NUMERIC="en_US.UTF-8"
LC_TIME="en_US.UTF-8"
LC_COLLATE="en_US.UTF-8"
LC_MONETARY="en_US.UTF-8"
LC_MESSAGES="en_US.UTF-8"
LC_PAPER="en_US.UTF-8"
LC_NAME="en_US.UTF-8"
LC_ADDRESS="en_US.UTF-8"
LC_TELEPHONE="en_US.UTF-8"
LC_MEASUREMENT="en_US.UTF-8"
LC_IDENTIFICATION="en_US.UTF-8"
LC_ALL=
root@CRIS-CAT:# locale-gen en_US en_US.UTF-8
Generating locales...
  en_US.ISO-8859-1... done
  en_US.UTF-8... up-to-date
Generation complete.
root@CRIS-CAT:# dpkg-reconfigure locales 
Generating locales...
  en_US.ISO-8859-1... up-to-date
  en_US.UTF-8... up-to-date
Generation complete.
root@CRIS-CAT:#