首先查看当前版本信息

# uname -a

Linux localhost.localdomain3.10.0-123.el7.x86_64 #1 SMP Mon Jun 30 12:09:22 UTC 2014 x86_64 x86_64 x86_64GNU/Linux

# cat/etc/redhat-release

CentOS Linux release 7.0.1406 (Core)

通过yum命令进行系统升级

[root@ZZSRV2 ~]# yum update →更新软件包不带任何参数的选项update可以更新所有已安装的软件包

Loaded plugins: fastestmirror, langpacks

base | 3.6 kB 00:00

extras | 3.3 kB 00:00

updates | 3.4 kB 00:00

updates/7/x86_64/primary_db | 2.8 MB 00:03

Loading mirror speeds from cached hostfile

* base: mirrors.neusoft.edu.cn

* extras: mirrors.skyshe.cn

* updates: mirrors.neusoft.edu.cn

Resolving Dependencies

--> Running transaction check

---> Package dhclient.x86_64 12:4.2.5-27.el7.centos will be updated

---> Package dhclient.x86_64 12:4.2.5-27.el7.centos.1 will be an update

---> Package dhcp-common.x86_64 12:4.2.5-27.el7.centos will be updated

---> Package dhcp-common.x86_64 12:4.2.5-27.el7.centos.1 will be an update

........

.......(部分省略)

Dependencies Resolved


================================================================================

Package Arch Version Repository

Size

================================================================================

Updating:

dhclient x86_64 12:4.2.5-27.el7.centos.1 updates 276 k

dhcp-common x86_64 12:4.2.5-27.el7.centos.1 updates 169 k

dhcp-libs x86_64 12:4.2.5-27.el7.centos.1 updates 126 k

kpatch noarch 0.1.10-1.el7_0 updates 8.2 k

nss-util x86_64 3.16.2-1.el7_0 updates 69 k

openssl x86_64 1:1.0.1e-34.el7_0.4 updates 705 k

openssl-libs x86_64 1:1.0.1e-34.el7_0.4 updates 940 k

yum-plugin-fastestmirror noarch 1.1.31-25.el7_0 updates 28 k

yum-utils noarch 1.1.31-25.el7_0 updates 111 k

.................

.........(部分省略)

Transaction Summary

================================================================================

Upgrade 17 Packages


Total download size: 4.6 M

Is this ok [y/d/N]: y

Downloading packages:

Delta RPMs disabled because /usr/bin/applydeltarpm not installed.

(1/17): dhcp-common-4.2.5-27.el7.centos.1.x86_64.rpm | 169 kB 00:00

(2/17): dhclient-4.2.5-27.el7.centos.1.x86_64.rpm | 276 kB 00:01

(3/17): kpatch-0.1.10-1.el7_0.noarch.rpm | 8.2 kB 00:00

(4/17): libgcc-4.8.2-16.2.el7_0.x86_64.rpm | 86 kB 00:00

(5/17): dhcp-libs-4.2.5-27.el7.centos.1.x86_64.rpm | 126 kB 00:01

(6/17): libstdc++-4.8.2-16.2.el7_0.x86_64.rpm | 288 kB 00:00

.................

...........(部分省略)

--------------------------------------------------------------------------------

Total 649 kB/s | 4.6 MB 00:07

Running transaction check

Running transaction test

Transaction test succeeded

Running transaction

Warning: RPMDB altered outside of yum.

Updating : nss-util-3.16.2-1.el7_0.x86_64 1/34

Updating : 12:dhcp-libs-4.2.5-27.el7.centos.1.x86_64 2/34

Updating : nss-softokn-freebl-3.16.2-1.el7_0.x86_64 3/34

Updating : nss-softokn-3.16.2-1.el7_0.x86_64 4/34

.......................

.....................

.................(部分省略)

Verifying : yum-utils-1.1.31-24.el7.noarch 34/34


Updated:

dhclient.x86_64 12:4.2.5-27.el7.centos.1

dhcp-common.x86_64 12:4.2.5-27.el7.centos.1

dhcp-libs.x86_64 12:4.2.5-27.el7.centos.1

kpatch.noarch 0:0.1.10-1.el7_0

libgcc.x86_64 0:4.8.2-16.2.el7_0

libgomp.x86_64 0:4.8.2-16.2.el7_0

libstdc++.x86_64 0:4.8.2-16.2.el7_0

nss.x86_64 0:3.16.2-2.el7_0

nss-softokn.x86_64 0:3.16.2-1.el7_0

...........

（部分省略)

Complete!

重新启动之后，进行验证

[root@ZZSRV2 ~]# uname -a

Linux localhost.localdomain3.10.0-123.6.3.el7.x86_64 #1 SMP Wed Aug 6 21:12:36 UTC 2014 x86_64 x86_64x86_64 GNU/Linux

[root@ZZSRV2 ~]# cat /etc/redhat-release

CentOS Linux release 7.0.1406 (Core)