hi Alan: 2014-07-08 1:02 GMT+08:00 Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>: > On Tue, 8 Jul 2014, loody wrote: > >> > An alternative is to write a positive value, such as 240000, to >> > >> > /sys/block/sdX/events_poll_msecs >> > >> > where X is replaced with the proper drive letter. (240000 ms = 240 s = >> > 4 m.) I'm not sure this will work, but it's worth a try. >> >> I cannot find events_poll_msecs you mentioned in my system. >> Is this capability related to kernel version? >> ( my kernel version is 2.6.38.8 ) > > Well, the in-kernel disk events mechanism was added in 2.6.38, but it > may not have been implemented for your type of drive. You are correct. i can see events_poll_msecs when I change my kernel to 3.8.0 But the device still disconnect. I have some question. 1. when I cat /sys/block/sdX/events, I get the answer as media_change. is there any events type we can choose, such as read capability or inquiry. > > Probably you don't actually need to do a read. Simply opening the > device file ought to be sufficient. 2. the open device you mean is like open(/dev/sda1)? thanks for all your kind help, -- Regards, -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html