ipa-ca-install: 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

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/ipa-ca-install - from package: ipa-server

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