pear: 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/pear - from package: php54w-pear
/usr/bin/pear - from package: php55w-pear
/usr/bin/pear - from package: php56w-pear
/usr/bin/pear - from package: php70w-pear
/usr/bin/pear - from package: php-pear

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

On Debian possible default full paths are:

/usr/bin/pear - from package: php-pear

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

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