ods-signer: 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/sbin/ods-signer - from package: opendnssec

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

On Debian possible default full paths are:

/usr/sbin/ods-signer - from package: opendnssec-signer

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

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