rpms2solv: 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/rpms2solv - from package: libsolv-tools

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

On Debian possible default full paths are:

/usr/bin/rpms2solv - from package: libsolv-tools

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

Error in other languages:
rpms2solv: bevel nie gevind nie
rpms2solv: comandă negăsită
rpms2solv: comando não encontrado
rpms2solv: commande introuvable
rpms2solv: command not found
rpms2solv: käsku ei ole
rpms2solv: không tìm thấy lệnh
rpms2solv: komanda nerasta
rpms2solv: Kommando nicht gefunden.
rpms2solv: kommandot finns inte
rpms2solv: komut yok
rpms2solv: nie znaleziono polecenia
rpms2solv: níor aimsíodh an t-ordú
rpms2solv: no se encontró la orden
rpms2solv: no s'ha trobat l'ordre
rpms2solv: opdracht niet gevonden
rpms2solv: parancs nem található
rpms2solv: perintah tidak ditemukan
rpms2solv: príkaz nenájdený
rpms2solv: příkaz nenalezen
rpms2solv: команда не найдена
rpms2solv: командата не е открита
rpms2solv: 命令找不到
rpms2solv: コマンドが見つかりません