[sheepdog] the mounted vm of using sheepfs which open the object_cache became Read-only file system

[周鹏]

>> It can know from the log that "volume_do_sync" will do CREATE_AND_WRITE_OBJ and then write something to the cache.
>> In order to further confirmation, the source code is really to do so.
>> But when and how did the vm became Read-only file system, i can not understand.So please help me to analyze the cause,thanks.

>If it is snapshot, it is read-only vdi.

>> BTW,when i test the sheepdog, i often meet the vm became Read-only.So another question, what can cause a read_only?


>Please use latest stable-0.7 or stable-0.6 branch and report problems if any.

Yeah, i have updated the sheepdog to version 0.7.1_1_g66102e5.
The same problem still exists.
Under the path of "/home/centos6/root", i excute:

[root at sheep-dell root]# echo aa>test.txt
-bash: test.txt: Read-only file system

At the same time, sheepfs printed:
volume_do_sync(306): failed to flush vdi 7c7833
volume_do_sync(306): failed to flush vdi 7c7833

gataway log:

Aug 26 17:33:47  DEBUG [main] client_handler(786) 1, rx 0, tx 3
Aug 26 17:33:47  DEBUG [main] finish_rx(590) 48, 127.0.0.1:49869
Aug 26 17:33:47  DEBUG [main] queue_request(347) WRITE_OBJ, 1
Aug 26 17:33:47  DEBUG [gway 13163] do_process_work(1334) 3, 7c78330000029d, 1
Aug 26 17:33:47  DEBUG [gway 13163] gateway_forward_request(267) 7c78330000029d
Aug 26 17:33:47  DEBUG [gway 13163] sockfd_cache_get_long(372) 192.168.10.41:7010, idx 0
Aug 26 17:33:47  DEBUG [gway 13163] sockfd_cache_get_long(372) 192.168.10.45:7010, idx 0
Aug 26 17:33:47  DEBUG [gway 13163] sockfd_cache_get_long(372) 192.168.10.47:7010, idx 0
Aug 26 17:33:47  DEBUG [gway 13163] gateway_forward_request(320) nr_sent 3, err 0
Aug 26 17:33:47  DEBUG [gway 13163] wait_forward_request(195) 0, revents 1
Aug 26 17:33:47  DEBUG [gway 13163] sockfd_cache_put_long(406) 192.168.10.41:7010 idx 0
Aug 26 17:33:47  DEBUG [gway 13163] write_info_update(115) 3, 0
Aug 26 17:33:47  DEBUG [gway 13163] wait_forward_request(195) 0, revents 1
Aug 26 17:33:47  DEBUG [gway 13163] sockfd_cache_put_long(406) 192.168.10.45:7010 idx 0
Aug 26 17:33:47  DEBUG [gway 13163] write_info_update(115) 2, 0
Aug 26 17:33:47  DEBUG [gway 13163] wait_forward_request(195) 0, revents 1
Aug 26 17:33:47  DEBUG [gway 13163] sockfd_cache_put_long(406) 192.168.10.47:7010 idx 0
Aug 26 17:33:47  DEBUG [gway 13163] write_info_update(115) 1, 0
Aug 26 17:33:47  DEBUG [main] client_handler(786) 4, rx 0, tx 3
Aug 26 17:33:47  DEBUG [main] finish_tx(677) connection from: 48, 127.0.0.1:49869

I used original vm and the clone vm  of using command "collie vdi clone centos6 centos6_clone -s 1", they both go wrong.