iscsi-ls: 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/iscsi-ls - from package: libiscsi-utils

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

On Debian possible default full paths are:

/usr/bin/iscsi-ls - from package: libiscsi-bin

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

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