rdma_xclient: 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/rdma_xclient - from package: librdmacm-utils

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

On Debian possible default full paths are:

/usr/bin/rdma_xclient - from package: rdmacm-utils

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