centos7在upgrade的时候显示：Delta RPMs disabled....详见内容？

Question

错误信息在第6行，从代码行开始数，空行不算。
即： Delta RPMs disabled because /usr/bin/applydeltarpm not installed.

前面有其他安装信息，太多，略去
.......
Install   1 Package
Upgrade  66 Packages

Total download size: 104 M
Is this ok [y/d/N]: y
Downloading packages:
Delta RPMs disabled because /usr/bin/applydeltarpm not installed.
lvm2-2.02.115-3.el7_1.1.x86_64.rpm                                                                                            | 897 kB  00:00:52     
gnutls-3.3.8-12.el7_1.1.x86_64.rpm                                                                                            | 662 kB  00:02:07     
kernel-tools-libs-3.10.0-229.14.1.el7.x86_64.rpm                                                                              | 1.3 MB  00:00:45 ... 
kernel-tools-libs-3.10.0-229.14.1.el7.x86_64.rpm                                                                              | 591 kB  00:00:32 ... 
openldap-2.4.39-7.el7.centos.x86_64.rpm                                                                                       | 233 kB  00:00:36 ... 
openldap-2.4.39-7.el7.centos.x86_64.rpm                                                                                       | 195 kB  00:00:33 ... 
coreutils-8.22-12.el7_1.2.x86_64.rpm                                                                                          |    0 B  00:00:30 ... 
coreutils-8.22-12.el7_1.2.x86_64.rpm 
...... 
后面有其他安装信息，太多，略去
        

Answer 1

# yum provides '*/applydeltarpm'
# yum install deltarpm

Also if No Presto metadata available for base. appears, try

# yum provides '*/applydeltarpm'

And

# yum install deltarpm

Answer 2

This is not an error message