mkmapfile: command not found

Have You tried accessing the binary with the full path?

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/mkmapfile - from package: perl-Unicode-Map

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