flickr_upload: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/flickr_upload - from package: perl-Flickr-Upload

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/flickr_upload - from package: libflickr-upload-perl

You may install the required package with command apt-get install {package}

Error in other languages:
flickr_upload: bevel nie gevind nie
flickr_upload: comandă negăsită
flickr_upload: comando não encontrado
flickr_upload: commande introuvable
flickr_upload: command not found
flickr_upload: käsku ei ole
flickr_upload: không tìm thấy lệnh
flickr_upload: komanda nerasta
flickr_upload: Kommando nicht gefunden.
flickr_upload: kommandot finns inte
flickr_upload: komut yok
flickr_upload: nie znaleziono polecenia
flickr_upload: níor aimsíodh an t-ordú
flickr_upload: no se encontró la orden
flickr_upload: no s'ha trobat l'ordre
flickr_upload: opdracht niet gevonden
flickr_upload: parancs nem található
flickr_upload: perintah tidak ditemukan
flickr_upload: príkaz nenájdený
flickr_upload: příkaz nenalezen
flickr_upload: команда не найдена
flickr_upload: командата не е открита
flickr_upload: 命令找不到
flickr_upload: コマンドが見つかりません