MooseFS热备元数据节点设计与实现

Design and Implementation of MooseFS Hot Standby Master

针对MooseFS元数据节点的单点故障问题,对MooseFS源码进行改造,为其增加一个热备的备元数据节点,并通过主备之间同步元数据,备节点回放操作日志等技术使得备元数据节点内存中的元数据时刻跟主元数据节点保持一致。当主元数据节点发生故障切换到备元数据节点后,备元数据节点无需从本地加载元数据即可快速接替主元数据节点对外提供服务。测试结果表明,备元数据节点本地和内存中的元数据均与主元数据节点保持一致,且故障恢复时间小于1s。

Aiming at the single point of failure problem of the MooseFS master, a hot standby master is added for MooseFS through modifying the source code. By synchronizing the metadata between the primary and standby master and the standby master replay log, the standby master’s metadata in memory are always consistent with the master’s. After the primary master fails over to the standby master, the standby master can quickly take over services from the primary master without loading the metadata from the local. Test results show that the metadata of the standby master in the local and in memory are consistent with the primary master, and the time of failure recovery is less than 1 second.