pmsignal: 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/libexec/pcp/bin/pmsignal - from package: pcp

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

On Debian possible default full paths are:

/usr/lib/pcp/bin/pmsignal - from package: pcp

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

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