yes, there is a tool graceful_stop.sh to graceful stop regionserver, and can move the regions back to the rs after rs come back. but i can not find the relation with drain region servers...
i think drain region servers function is good, but can not think up with a pracital use case At 2016-04-26 16:01:55, "Dejan Menges" <dejan.men...@gmail.com> wrote: >One of use cases we use it is graceful stop of regionserver - you unload >regions from the server before you restart it. Of course, after restart you >expect HBase to move regions back. > >Now I'm not really remembering correctly, but I kinda remember that one of >the features was at least that it will move back regions which were already >there, hence not destroy too much block locality. > >On Tue, Apr 26, 2016 at 8:15 AM WangYQ <wangyongqiang0...@163.com> wrote: > >> thanks >> in hbase 0.99.0, I find the rb file: draining_servers.rb >> >> >> i have some suggestions on this tool: >> 1. if I add rs hs1 to draining_servers, when hs1 restart, the zk node >> still exists in zk, but hmaster will not treat hs1 as draining_servers >> i think when we add a hs to draining_servers, we do not need to store >> the start code in zk, just store the hostName and port >> 2. we add hs1 to draining_servers, but if hs1 always restart, we will >> need to add hs1 several times >> when we need to delete the draining_servers info of hs1, we will need >> to delete hs1 several times >> >> >> >> finally, what is the original motivation of this tool, some scenario >> descriptions are good. >> >> >> >> >> >> >> At 2016-04-26 11:33:10, "Ted Yu" <yuzhih...@gmail.com> wrote: >> >Please take a look at: >> >bin/draining_servers.rb >> > >> >On Mon, Apr 25, 2016 at 8:12 PM, WangYQ <wangyongqiang0...@163.com> >> wrote: >> > >> >> in hbase, I find there is a "drain regionServer" feature >> >> >> >> >> >> if a rs is added to drain regionServer in ZK, then regions will not be >> >> move to on these regionServers >> >> >> >> >> >> but, how can a rs be add to drain regionServer, we add it handly or >> rs >> >> will add itself automaticly >>
