to join the two. ● Nebdclient: Forward the requests from QEMU and curve-NBD to the specified NEBDServer through Unix Domain sockets. ● Nebdserver: Accepts requests from NEBDClient and calls Curve Client NEBDClients. 3. Through the above splitting, NebdClient replaces Curve Client and directly interfaces with upper services. There is no logical processing in NEBDClient, it just proxy requests and has limited limited retries, which ensuring that NEBDClient needs no change. To upgrade curve-client, you only need to restart the NEBDServer, which affects services in few seconds. ## CurveBS IO processing flow Overall

/13b6145ac1674f4b66b9481848c048a7/p12_1.jpg) ## Curve块存储 ## 在线升级设计 1. 客户端分成 NebdClient 与 NebdServer 两部分 2. NebdClient只做简单的转发 3. NebdServer实现大部分的客户端逻辑 ![Image](/uploads/documents/1/3/b/6/13b6145a