Re: [HPDD-discuss] Clean shutdown

maybe this is what you are looking for: during recovery on the MDS: cat /proc/fs/lustre/mds/lustrefs-MDT0000/recovery_status" shows the number of clients already connected and the number the server expects.

during normal operation cat /proc/fs/lustre/mds/lustrefs-MDT0000/num_exports shows the number of exports (If I recall correctly, the MGS is a client as well in this context)

On 07/06/2015 05:16 PM, Scott Nolin wrote: > the 'lshowmount' command on the servers can do this. > > However I sometimes have seen where lshowmount doesn't show any > connected clients, but they obviously still are. So maybe there's a > lower-level way than that utility that's better. > > Scott > > On 7/6/2015 10:09 AM, Jérôme BECOT wrote: >> That's how i proceed, but i had kernel crashes on the MDS so I >> unmounted >> and remounted it and it recovers >> >> No way to check wether Lustre servers considers any client still >> connect >> or not ? >> >> Le 04/07/2015 04:43, Kurt Strosahl a écrit : >>> Hi, >>> >>> I just did a clean shutdown/startup of two lustre file systems >>> last weekend (also for electrical work). The order that I've found >>> most effective is to first shutdown all the clients, then unmount the >>> osts/shutdown the oss systems, then unmount the mdt/mgs and shut down >>> that system. On the up I've found that turning on the mdt/mgs system, >>> letting it mount up. Then mounting the osts (my oss systems don't >>> mount lustre on boot). Once the last ost to be mounted looks like it >>> has finished any recovery it needs to do I mount a single client and >>> make sure it can see the entire system... and then go from there with >>> the rest of the clients. >>> >>> Since all the lustre clients I have are in the same room as the lustre >>> file system itself I don't have to check for stray mounts (I just walk >>> around the room looking for systems that are still on, and then power >>> them off). >>> >>> Good luck, >>> Kurt J. Strosahl >>> System Administrator >>> Scientific Computing Group, Thomas Jefferson National Accelerator >>> Facility >>> >>> >>> Message: 1 >>> Date: Fri, 03 Jul 2015 13:49:32 +0200 >>> From: J?r?me BECOT <jerome.becot(a)inserm.fr&gt; >>> To: HPDD-discuss(a)ml01.01.org >>> Subject: [HPDD-discuss] Clean shutdown >>> Message-ID: <559676CC.1060009(a)inserm.fr&gt; >>> Content-Type: text/plain; charset=utf-8; format=flowed >>> >>> Hi there, >>> >>> We are running a small lustre system (1MGS/MDS + 2 OSTs). I haven't >>> found the information, so i ask you : >>> >>> What is the good order to shutdown the whole system (for electrical >>> maintenance ...) when you run a combined MGT/MDT : >>> - disconnect the clients >>> - is there any way to check if there is a client still connected ? >>> - unmount the MGT/MDT >>> - unmount the OSTs >>> - ... poweroff all the servers >>> - mount the OSTs >>> - then the MGT/MDT >>> - then the clients ? >>> >>> or should I stop the ost first and mount them last ? >>> >>> Thanks >>> >>> >> > > > > > _______________________________________________ > HPDD-discuss mailing list > HPDD-discuss(a)lists.01.org > https://lists.01.org/mailman/listinfo/hpdd-discuss _______________________________________________ HPDD-discuss mailing list HPDD-discuss(a)lists.01.org https://lists.01.org/mailman/listinfo/hpdd-discuss