Ubuntu 14.04 Cloud Server - Disks gone Read Only

Question

Disks on our cloud server with our web host went read-only this morning for no apparent reason. Following that a reboot to try and rectify the issue resulted in a non-bootable system.

Our Web Host seem incapable of getting to the bottom of the issue.

Before the reboot we managed to grab this:

[3165585.488502] hv_storvsc vmbus_0_2: cmd 0x2a scsi status 0x2 srb status 0x82
[3165585.488507] hv_storvsc vmbus_0_2: stor pkt ffff88003596e300 autosense data valid - len 18
[3165585.488509] storvsc: Sense Key : Unit Attention [current] 
[3165585.488512] storvsc: Add. Sense: Changed operating definition
[3165585.488520] sd 2:0:0:0: Warning! Received an indication that the operating parameters on this target have changed. The Linux SCSI layer does not automatically adjust these parameters.
[3165756.924419] INPUT DROP: IN=eth0 OUT= MAC=00:1d:db:b7:1d:9b:88:f0:31:cb:64:41:08:00 SRC=217.170.41.29 DST=109.228.21.191 LEN=40 TOS=0x00 PREC=0x00 TTL=55 ID=12012 PROTO=TCP SPT=59005 DPT=445 WINDOW=512 RES=0x00 SYN URGP=0 
[3165865.066921] INPUT DROP: IN=eth0 OUT= MAC=00:1d:db:b7:1d:9b:88:f0:31:cb:67:c1:08:00 SRC=91.121.211.21 DST=109.228.21.191 LEN=44 TOS=0x00 PREC=0x00 TTL=51 ID=38209 PROTO=TCP SPT=80 DPT=31156 WINDOW=16384 RES=0x00 ACK SYN URGP=0 
[3165892.828977] INPUT DROP: IN=eth0 OUT= MAC=00:1d:db:b7:1d:9b:88:f0:31:cb:67:c1:08:00 SRC=80.85.84.75 DST=109.228.21.191 LEN=40 TOS=0x00 PREC=0x00 TTL=248 ID=28453 PROTO=TCP SPT=44001 DPT=5800 WINDOW=1024 RES=0x00 SYN URGP=0 
[3165936.889407] hv_storvsc vmbus_0_2: cmd 0x35 scsi status 0x2 srb status 0x82
[3165936.889413] hv_storvsc vmbus_0_2: stor pkt ffff88003596c000 autosense data valid - len 18
[3165936.889416] storvsc: Sense Key : Unit Attention [current] 
[3165936.889419] storvsc: Add. Sense: Changed operating definition
[3165936.889429] sd 2:0:0:0: Warning! Received an indication that the operating parameters on this target have changed. The Linux SCSI layer does not automatically adjust these parameters.
[3165936.889437] end_request: I/O error, dev sda, sector 38756424
[3165936.889497] Aborting journal on device dm-0-8.
[3165936.891502] EXT4-fs error (device dm-0): ext4_journal_check_start:56: Detected aborted journal
[3165936.891536] EXT4-fs (dm-0): Remounting filesystem read-only

I think hardware, and everything I search for on the net seems to point to disks but the webhost says not, any thoughts?

Answer 1

The messages logged only inform of some change in the SAS bus (presumably it is SAS or emulation of SAS), it can mean different things including that the disk had gone away as well as just a change in some parameter that is completely benign in the SAS expander/controller.

There isn't much to go on with these messages alone.

The fact that the journal was stopped and fs remounted to read-only indicates some errors were returned but they are not logged here so it is impossible to know.