• 准备工作
  假设有一个三台服务器的glusterfs集群，volume类型为副本数为3的分布式复制卷
  三台server的ip为：server1：192.168.100.2，server2：192.168.100.3, server3：192.168.100.4
  glusterfs的版本为3.7.12
  需要升级到的版本为3.8.0
  note：glusterfs-3.8.0暂时没有提供官方repo包，需要自己安装rpm包
• 策略
  互为副本的集群，需要依次升级，实现glusterfs的服务不中断

这里，先升级server1

• 升级前
  1)关闭glusterfs的self-heal功能
  [root@~]# gluster v set testvol cluster.entry-self-heal off
  [root@~]# gluster v set testvol cluster.data-self-heal off
  [root@~]# gluster v set testvol cluster.metadata-self-heal off
  2)关闭glusterfs的服务
  Stop all glusterd, glusterfsd and glusterfs processes on server1.
  3)卸载glusterfs-3.7.12的rpm包
  [root@~]# yum remove glusterfs-libs-3.7.12-1.el7.x86_64
  4)安装glusterfs-3.8.0
  [root@~]# yum install http://buildlogs.centos.org/centos/7/storage/x86_64/gluster-3.8/glusterfs-libs-3.8.0-1.el7.x86_64.rpm
  [root@~]# yum install http://buildlogs.centos.org/centos/7/storage/x86_64/gluster-3.8/glusterfs-client-xlators-3.8.0-1.el7.x86_64.rpm
  [root@~]# yum install http://buildlogs.centos.org/centos/7/storage/x86_64/gluster-3.8/glusterfs-3.8.0-1.el7.x86_64.rpm
  [root@~]# yum install http://buildlogs.centos.org/centos/7/storage/x86_64/gluster-3.8/glusterfs-api-3.8.0-1.el7.x86_64.rpm
  [root@~]# yum install http://buildlogs.centos.org/centos/7/storage/x86_64/gluster-3.8/glusterfs-cli-3.8.0-1.el7.x86_64.rpm
  [root@~]# yum install http://buildlogs.centos.org/centos/7/storage/x86_64/gluster-3.8/glusterfs-fuse-3.8.0-1.el7.x86_64.rpm
  [root@~]# yum install http://buildlogs.centos.org/centos/7/storage/x86_64/gluster-3.8/userspace-rcu-0.7.16-1.el7.x86_64.rpm
  [root@~]# yum install http://buildlogs.centos.org/centos/7/storage/x86_64/gluster-3.8/glusterfs-server-3.8.0-1.el7.x86_64.rpm
  5)查看glusterfs版本，看看是否升级成功
  [root@~]# gluster --version
  6)重启glusterfsd服务
  [root@~]# service glusterd start

然后，依次升级server2，server3 即可完成glusterfs的升级