pmlogreduce: 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/pmlogreduce - 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/pmlogreduce - from package: pcp

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

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