Linux下没有sz和rz命令

yum install lrzsz

[root@xxt downloads]# yum install lrzsz
Loaded plugins: fastestmirror
Determining fastest mirrors
* base: mirrors.cqu.edu.cn
* extras: mirrors.cqu.edu.cn
* updates: mirrors.cqu.edu.cn
base                                                     | 3.7 kB     00:00
extras                                                   | 3.3 kB     00:00
extras/primary_db                                        |  30 kB     00:00
updates                                                  | 3.4 kB     00:00
updates/primary_db                                       | 3.6 MB     00:00
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package lrzsz.i686 0:0.12.20-27.1.el6 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

================================================================================
Package         Arch           Version                    Repository      Size
================================================================================
Installing:
lrzsz           i686           0.12.20-27.1.el6           base            66 k

Transaction Summary
================================================================================
Install       1 Package(s)

Total download size: 66 k
Installed size: 150 k
Is this ok [y/N]: y
Downloading Packages:
lrzsz-0.12.20-27.1.el6.i686.rpm                          |  66 kB     00:00
warning: rpmts_HdrFromFdno: Header V3 RSA/SHA256 Signature, key ID c105b9de: NOKEY
Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6
Importing GPG key 0xC105B9DE:
Userid : CentOS-6 Key (CentOS 6 Official Signing Key) <centos-6-key@centos.org>
Package: centos-release-6-5.el6.centos.11.1.i686 (@anaconda-CentOS-201311271240.i386/6.5)
From   : /etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-6
Is this ok [y/N]: y
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
Installing : lrzsz-0.12.20-27.1.el6.i686                                  1/1
Verifying  : lrzsz-0.12.20-27.1.el6.i686                                  1/1

Installed:
lrzsz.i686 0:0.12.20-27.1.el6
95d0

Complete!

[root@xxt downloads]# rz
rz waiting to receive.
Starting zmodem transfer.  Press Ctrl+C to cancel.
Transferring spark-2.1.0-bin-hadoop2.7.tgz...
100%  191051 KB    4776 KB/sec    00:00:40       0 Errors