linux下yum upgrade、yum update有什么区别?

yum upgrade、yum update在linux中都可以用更新新软件安装包或升级软件了,那么这yum upgrade、yum update有什么区别呢?下面我们就一起来看看吧.

在网上看到有人如下总结:

yum -y update

升级所有包,改变软件设置和系统设置,系统版本内核都升级

yum -y upgrade

升级所有包,不改变软件设置和系统设置,系统版本升级,内核不改变.

测试一下所谓yum upgrade于yum update的区别:

基本信息:

1. [root@localhost ~]# uname -a    
2. Linux localhost.localdomain 2.6.32-358.el6.x86_64 #1 SMP Fri Feb 22 00:31:26 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux 
3. [root@localhost ~]# cat /etc/redhat-release  
4. CentOS release 6.4 (Final) 
5. man yum： 
6. --obsoletes:This option only has affect for an update, it enables yum´s obsoletes processing logic. For more information see the update command above. 
7. Configuration Option: obsoletes 
8. upgrade:Is the same as the update command with the --obsoletes flag set. See update for more details. 
9. update:If run without any packages, update will update every currently installed package.  If one or more packages or package globs are specified, Yum will only update the listed packages.While updating packages,yum will ensure that all dependencies are satisfied. (See Specifying package names for more information) 
10. If the packages or globs specified match to packages which are not currently installed then  update  will not  install  them. update operates on groups, files, provides and filelists just like the "install" command. 
11. If the main obsoletes configure option is true (default) or the --obsoletes  flag  is  present  yum  will include  package obsoletes  in  its  calculations - this makes it better for distro-version changes, for example: upgrading from somelinux 8.0 to somelinux 9. 
12. Note that "update" works on installed packages first, and only if there are no matches does it  look  for available packages. The difference is most noticeable when you do "update foo-1-2" which will act exactly as "update foo" if foo-1-2 is installed. You can use the "update-to" if you’d prefer that nothing  happen in the above case. 
13. yum upgrade： 
14. Installed: 
15.   kernel.x86_64 0:2.6.32-504.12.2.el6                                                                                                
16. Dependency Installed: 
17.   libtasn1.x86_64 0:2.3-6.el6_5          p11-kit.x86_64 0:0.18.5-2.el6_5.2           p11-kit-trust.x86_64 0:0.18.5-2.el6_5.2        
18.   pkgconfig.x86_64 1:0.23-9.1.el6        shared-mime-info.x86_64 0:0.70-6.el6       
19. Updated: 
20.   audit.x86_64 0:2.3.7-5.el6                                         audit-libs.x86_64 0:2.3.7-5.el6                                 
21.   authconfig.x86_64 0:6.1.12-19.el6                                  bash.x86_64 0:4.1.2-29.el6                                      
22.   binutils.x86_64 0:2.20.51.0.2-5.42.el6                             ca-certificates.noarch 0:2014.1.98-65.1.el6                     
23.   centos-release.x86_64 0:6-6.el6.centos.12.2                        chkconfig.x86_64 0:1.3.49.3-2.el6_4.1                           
24.   coreutils.x86_64 0:8.4-37.el6                                      coreutils-libs.x86_64 0:8.4-37.el6                              
25.   cpio.x86_64 0:2.10-12.el6_5                                        cronie.x86_64 0:1.4.4-12.el6                                    
26.   cronie-anacron.x86_64 0:1.4.4-12.el6                               cryptsetup-luks.x86_64 0:1.2.0-11.el6                           
27.   cryptsetup-luks-libs.x86_64 0:1.2.0-11.el6                         curl.x86_64 0:7.19.7-40.el6_6.4                                 
28.   cyrus-sasl.x86_64 0:2.1.23-15.el6_6.1                              cyrus-sasl-lib.x86_64 0:2.1.23-15.el6_6.1                       
29.   db4.x86_64 0:4.7.25-18.el6_4                                       db4-utils.x86_64 0:4.7.25-18.el6_4                              
30.   dbus-glib.x86_64 0:0.86-6.el6                                      device-mapper.x86_64 0:1.02.90-2.el6_6.1                        
31.   device-mapper-event.x86_64 0:1.02.90-2.el6_6.1                     device-mapper-event-libs.x86_64 0:1.02.90-2.el6_6.1             
32.   device-mapper-libs.x86_64 0:1.02.90-2.el6_6.1                      device-mapper-multipath.x86_64 0:0.4.9-80.el6_6.3               
33.   device-mapper-multipath-libs.x86_64 0:0.4.9-80.el6_6.3             device-mapper-persistent-data.x86_64 0:0.3.2-1.el6              
34.   dhclient.x86_64 12:4.1.1-43.P1.el6.centos.1                        dhcp-common.x86_64 12:4.1.1-43.P1.el6.centos.1                  
35.   dracut.noarch 0:004-356.el6_6.1                                    dracut-kernel.noarch 0:004-356.el6_6.1                          
36.   e2fsprogs.x86_64 0:1.41.12-21.el6                                  e2fsprogs-libs.x86_64 0:1.41.12-21.el6                          
37.   efibootmgr.x86_64 0:0.5.4-12.el6                                   elfutils-libelf.x86_64 0:0.158-3.2.el6                          
38.   ethtool.x86_64 2:3.5-5.el6                                         file.x86_64 0:5.04-21.el6                                       
39.   file-libs.x86_64 0:5.04-21.el6                                     glib2.x86_64 0:2.28.8-4.el6                                     
40.   gnupg2.x86_64 0:2.0.14-8.el6                                       grep.x86_64 0:2.6.3-6.el6                                       
41.   grub.x86_64 1:0.97-93.el6                                          grubby.x86_64 0:7.0.15-7.el6                                    
42.   gzip.x86_64 0:1.3.12-22.el6                                        hwdata.noarch 0:0.233-11.1.el6                                  
43.   initscripts.x86_64 0:9.03.46-1.el6.centos.1                        iproute.x86_64 0:2.6.32-33.el6_6                                
44.   iptables.x86_64 0:1.4.7-14.el6                                     iptables-ipv6.x86_64 0:1.4.7-14.el6                             
45.   iputils.x86_64 0:20071127-17.el6_4.2                               iscsi-initiator-utils.x86_64 0:6.2.0.873-13.el6                 
46.   kernel-firmware.noarch 0:2.6.32-504.12.2.el6                       keyutils-libs.x86_64 0:1.4-5.el6                                
47.   kpartx.x86_64 0:0.4.9-80.el6_6.3                                   krb5-libs.x86_64 0:1.10.3-33.el6                                
48.   less.x86_64 0:436-13.el6                                           libblkid.x86_64 0:2.17.2-12.18.el6                              
49.   libcom_err.x86_64 0:1.41.12-21.el6                                 libcurl.x86_64 0:7.19.7-40.el6_6.4                              
50.   libdrm.x86_64 0:2.4.52-4.el6                                       libgcrypt.x86_64 0:1.4.5-11.el6_4                               
51.   libpciaccess.x86_64 0:0.13.3-0.1.el6                               libselinux.x86_64 0:2.0.94-5.8.el6                              
52.   libselinux-utils.x86_64 0:2.0.94-5.8.el6                           libss.x86_64 0:1.41.12-21.el6                                   
53.   libssh2.x86_64 0:1.4.2-1.el6_6.1                                   libudev.x86_64 0:147-2.57.el6                                   
54.   libuuid.x86_64 0:2.17.2-12.18.el6                                  libxml2.x86_64 0:2.7.6-17.el6_6.1                               
55.   logrotate.x86_64 0:3.7.8-17.el6                                    lvm2.x86_64 0:2.02.111-2.el6_6.1                                
56.   lvm2-libs.x86_64 0:2.02.111-2.el6_6.1                              mdadm.x86_64 0:3.3-6.el6_6.1                                    
57.   module-init-tools.x86_64 0:3.9-24.el6                              mysql-libs.x86_64 0:5.1.73-3.el6_5                              
58.   nspr.x86_64 0:4.10.6-1.el6_5                                       nss.x86_64 0:3.16.2.3-3.el6_6                                   
59.   nss-softokn.x86_64 0:3.14.3-22.el6_6                               nss-softokn-freebl.x86_64 0:3.14.3-22.el6_6                     
60.   nss-sysinit.x86_64 0:3.16.2.3-3.el6_6                              nss-tools.x86_64 0:3.16.2.3-3.el6_6                             
61.   nss-util.x86_64 0:3.16.2.3-2.el6_6                                 openldap.x86_64 0:2.4.39-8.el6                                  
62.   openssh.x86_64 0:5.3p1-104.el6_6.1                                 openssh-clients.x86_64 0:5.3p1-104.el6_6.1                      
63.   openssh-server.x86_64 0:5.3p1-104.el6_6.1                          pam.x86_64 0:1.1.1-20.el6                                       
64.   pciutils-libs.x86_64 0:3.1.10-4.el6                                plymouth.x86_64 0:0.8.3-27.el6.centos.1                         
65.   plymouth-core-libs.x86_64 0:0.8.3-27.el6.centos.1                  plymouth-scripts.x86_64 0:0.8.3-27.el6.centos.1                 
66.   policycoreutils.x86_64 0:2.0.83-19.47.el6_6.1                      postfix.x86_64 2:2.6.6-6.el6_5                                  
67.   procps.x86_64 0:3.2.8-30.el6                                       psmisc.x86_64 0:22.6-19.el6_5                                   
68.   python.x86_64 0:2.6.6-52.el6                                       python-libs.x86_64 0:2.6.6-52.el6                               
69.   python-urlgrabber.noarch 0:3.9.1-9.el6                             rpm.x86_64 0:4.8.0-38.el6_6                                     
70.   rpm-libs.x86_64 0:4.8.0-38.el6_6                                   rpm-python.x86_64 0:4.8.0-38.el6_6                              
71.   rsyslog.x86_64 0:5.8.10-10.el6_6                                   selinux-policy.noarch 0:3.7.19-260.el6_6.2                      
72.   selinux-policy-targeted.noarch 0:3.7.19-260.el6_6.2                setup.noarch 0:2.8.14-20.el6_4.1                                
73.   shadow-utils.x86_64 2:4.1.4.2-19.el6                               sudo.x86_64 0:1.8.6p3-15.el6                                    
74.   system-config-firewall-base.noarch 0:1.2.27-7.2.el6_6              sysvinit-tools.x86_64 0:2.87-5.dsf.el6                          
75.   tzdata.noarch 0:2015a-1.el6                                        udev.x86_64 0:147-2.57.el6                                      
76.   upstart.x86_64 0:0.6.5-13.el6_5.3                                  util-linux-ng.x86_64 0:2.17.2-12.18.el6                         
77.   xfsprogs.x86_64 0:3.1.1-16.el6                                     xz-libs.x86_64 0:4.999.9-0.5.beta.20091007git.el6               
78.   yum.noarch 0:3.2.29-60.el6.centos                                  yum-plugin-fastestmirror.noarch 0:1.1.30-30.el6                
79. Complete! 
80. [root@localhost ~]# reboot 
81. [root@localhost ~]# uname -a    
82. Linux localhost.localdomain 2.6.32-504.12.2.el6.x86_64 #内核升级了！ 
83. [root@localhost ~]# cat /etc/redhat-release  
84. CentOS release 6.6 (Final) 
85.  
86. yum update: 
87. Installed: 
88.   kernel.x86_64 0:2.6.32-504.12.2.el6                                                                                                
89. Dependency Installed: 
90.   libtasn1.x86_64 0:2.3-6.el6_5          p11-kit.x86_64 0:0.18.5-2.el6_5.2           p11-kit-trust.x86_64 0:0.18.5-2.el6_5.2        
91.   pkgconfig.x86_64 1:0.23-9.1.el6        shared-mime-info.x86_64 0:0.70-6.el6       
92. Updated: 
93.   audit.x86_64 0:2.3.7-5.el6                                         audit-libs.x86_64 0:2.3.7-5.el6                                 
94.   authconfig.x86_64 0:6.1.12-19.el6                                  bash.x86_64 0:4.1.2-29.el6                                      
95.   binutils.x86_64 0:2.20.51.0.2-5.42.el6                             ca-certificates.noarch 0:2014.1.98-65.1.el6                     
96.   centos-release.x86_64 0:6-6.el6.centos.12.2                        chkconfig.x86_64 0:1.3.49.3-2.el6_4.1                           
97.   coreutils.x86_64 0:8.4-37.el6                                      coreutils-libs.x86_64 0:8.4-37.el6                              
98.   cpio.x86_64 0:2.10-12.el6_5                                        cronie.x86_64 0:1.4.4-12.el6                                    
99.   cronie-anacron.x86_64 0:1.4.4-12.el6                               cryptsetup-luks.x86_64 0:1.2.0-11.el6                           
100.   cryptsetup-luks-libs.x86_64 0:1.2.0-11.el6                         curl.x86_64 0:7.19.7-40.el6_6.4                                 
101.   cyrus-sasl.x86_64 0:2.1.23-15.el6_6.1                              cyrus-sasl-lib.x86_64 0:2.1.23-15.el6_6.1                       
102.   db4.x86_64 0:4.7.25-18.el6_4                                       db4-utils.x86_64 0:4.7.25-18.el6_4                              
103.   dbus-glib.x86_64 0:0.86-6.el6                                      device-mapper.x86_64 0:1.02.90-2.el6_6.1                        
104.   device-mapper-event.x86_64 0:1.02.90-2.el6_6.1                     device-mapper-event-libs.x86_64 0:1.02.90-2.el6_6.1             
105.   device-mapper-libs.x86_64 0:1.02.90-2.el6_6.1                      device-mapper-multipath.x86_64 0:0.4.9-80.el6_6.3               
106.   device-mapper-multipath-libs.x86_64 0:0.4.9-80.el6_6.3             device-mapper-persistent-data.x86_64 0:0.3.2-1.el6              
107.   dhclient.x86_64 12:4.1.1-43.P1.el6.centos.1                        dhcp-common.x86_64 12:4.1.1-43.P1.el6.centos.1                  
108.   dracut.noarch 0:004-356.el6_6.1                                    dracut-kernel.noarch 0:004-356.el6_6.1                          
109.   e2fsprogs.x86_64 0:1.41.12-21.el6                                  e2fsprogs-libs.x86_64 0:1.41.12-21.el6                          
110.   efibootmgr.x86_64 0:0.5.4-12.el6                                   elfutils-libelf.x86_64 0:0.158-3.2.el6                          
111.   ethtool.x86_64 2:3.5-5.el6                                         file.x86_64 0:5.04-21.el6                                       
112.   file-libs.x86_64 0:5.04-21.el6                                     glib2.x86_64 0:2.28.8-4.el6                                     
113.   gnupg2.x86_64 0:2.0.14-8.el6                                       grep.x86_64 0:2.6.3-6.el6                                       
114.   grub.x86_64 1:0.97-93.el6                                          grubby.x86_64 0:7.0.15-7.el6                                    
115.   gzip.x86_64 0:1.3.12-22.el6                                        hwdata.noarch 0:0.233-11.1.el6                                  
116.   initscripts.x86_64 0:9.03.46-1.el6.centos.1                        iproute.x86_64 0:2.6.32-33.el6_6                                
117.   iptables.x86_64 0:1.4.7-14.el6                                     iptables-ipv6.x86_64 0:1.4.7-14.el6                             
118.   iputils.x86_64 0:20071127-17.el6_4.2                               iscsi-initiator-utils.x86_64 0:6.2.0.873-13.el6                 
119.   kernel-firmware.noarch 0:2.6.32-504.12.2.el6                       keyutils-libs.x86_64 0:1.4-5.el6                                
120.   kpartx.x86_64 0:0.4.9-80.el6_6.3                                   krb5-libs.x86_64 0:1.10.3-33.el6                                
121.   less.x86_64 0:436-13.el6                                           libblkid.x86_64 0:2.17.2-12.18.el6                              
122.   libcom_err.x86_64 0:1.41.12-21.el6                                 libcurl.x86_64 0:7.19.7-40.el6_6.4                              
123.   libdrm.x86_64 0:2.4.52-4.el6                                       libgcrypt.x86_64 0:1.4.5-11.el6_4                               
124.   libpciaccess.x86_64 0:0.13.3-0.1.el6                               libselinux.x86_64 0:2.0.94-5.8.el6                              
125.   libselinux-utils.x86_64 0:2.0.94-5.8.el6                           libss.x86_64 0:1.41.12-21.el6                                   
126.   libssh2.x86_64 0:1.4.2-1.el6_6.1                                   libudev.x86_64 0:147-2.57.el6                                   
127.   libuuid.x86_64 0:2.17.2-12.18.el6                                  libxml2.x86_64 0:2.7.6-17.el6_6.1                               
128.   logrotate.x86_64 0:3.7.8-17.el6                                    lvm2.x86_64 0:2.02.111-2.el6_6.1                                
129.   lvm2-libs.x86_64 0:2.02.111-2.el6_6.1                              mdadm.x86_64 0:3.3-6.el6_6.1                                    
130.   module-init-tools.x86_64 0:3.9-24.el6                              mysql-libs.x86_64 0:5.1.73-3.el6_5                              
131.   nspr.x86_64 0:4.10.6-1.el6_5                                       nss.x86_64 0:3.16.2.3-3.el6_6                                   
132.   nss-softokn.x86_64 0:3.14.3-22.el6_6                               nss-softokn-freebl.x86_64 0:3.14.3-22.el6_6                     
133.   nss-sysinit.x86_64 0:3.16.2.3-3.el6_6                              nss-tools.x86_64 0:3.16.2.3-3.el6_6                             
134.   nss-util.x86_64 0:3.16.2.3-2.el6_6                                 openldap.x86_64 0:2.4.39-8.el6                                  
135.   openssh.x86_64 0:5.3p1-104.el6_6.1                                 openssh-clients.x86_64 0:5.3p1-104.el6_6.1                      
136.   openssh-server.x86_64 0:5.3p1-104.el6_6.1                          pam.x86_64 0:1.1.1-20.el6                                       
137.   pciutils-libs.x86_64 0:3.1.10-4.el6                                plymouth.x86_64 0:0.8.3-27.el6.centos.1                         
138.   plymouth-core-libs.x86_64 0:0.8.3-27.el6.centos.1                  plymouth-scripts.x86_64 0:0.8.3-27.el6.centos.1                 
139.   policycoreutils.x86_64 0:2.0.83-19.47.el6_6.1                      postfix.x86_64 2:2.6.6-6.el6_5                                  
140.   procps.x86_64 0:3.2.8-30.el6                                       psmisc.x86_64 0:22.6-19.el6_5                                   
141.   python.x86_64 0:2.6.6-52.el6                                       python-libs.x86_64 0:2.6.6-52.el6                               
142.   python-urlgrabber.noarch 0:3.9.1-9.el6                             rpm.x86_64 0:4.8.0-38.el6_6                                     
143.   rpm-libs.x86_64 0:4.8.0-38.el6_6                                   rpm-python.x86_64 0:4.8.0-38.el6_6                              
144.   rsyslog.x86_64 0:5.8.10-10.el6_6                                   selinux-policy.noarch 0:3.7.19-260.el6_6.2                      
145.   selinux-policy-targeted.noarch 0:3.7.19-260.el6_6.2                setup.noarch 0:2.8.14-20.el6_4.1                                
146.   shadow-utils.x86_64 2:4.1.4.2-19.el6                               sudo.x86_64 0:1.8.6p3-15.el6                                    
147.   system-config-firewall-base.noarch 0:1.2.27-7.2.el6_6              sysvinit-tools.x86_64 0:2.87-5.dsf.el6                          
148.   tzdata.noarch 0:2015a-1.el6                                        udev.x86_64 0:147-2.57.el6   --Vevb.com                                   
149.   upstart.x86_64 0:0.6.5-13.el6_5.3                                  util-linux-ng.x86_64 0:2.17.2-12.18.el6                         
150.   xfsprogs.x86_64 0:3.1.1-16.el6                                     xz-libs.x86_64 0:4.999.9-0.5.beta.20091007git.el6               
151.   yum.noarch 0:3.2.29-60.el6.centos                                  yum-plugin-fastestmirror.noarch 0:1.1.30-30.el6                
152. Complete! 
153. [root@localhost ~]# uname -a 
154. Linux localhost.localdomain 2.6.32-504.12.2.el6.x86_64 #1 SMP Wed Mar 11 22:03:14 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux 
155. [root@localhost ~]# cat /etc/redhat-release  
156. CentOS release 6.6 (Final) 

结论:Centos6.4 升级到 Centos6.6 貌似 yum update 和 yum upgrade 均可.