Resize Linux Filesystem of attached/Protected device may cause unexpected reboot of Linux server during next backup of this device
説明
Unexpected Linux server reboot after resizing protected volume and running a backup of that volume.
System Logs:
========================================================= [3897303.600259] ------------[ cut here ]------------ [3897303.600266] kernel BUG at /var/lib/dkms/rapidrecovery-vss/6.3.0.5309/build/src/kernel/blksnap-block.c:56! [3897303.600274] invalid opcode: 0000 [#1] SMP [3897303.600284] Modules linked in: tcp_lp fuse joydev xt_CHECKSUM...... [3897303.600424] crct10dif_generic mgag200 drm_kms_helper syscopyarea sysfillrect...... [3897303.600479] CPU: 4 PID: 196997 Comm: Threadpool work Kdump: loaded Tainted: P W OE ------------ 3.10.0-862.el7.x86_64 #1 =========================================================
原因
Our module is compiled to the Kernel and constantly check the change-blocks on attached devices. When you resize volume that is still attached to our driver, it creates system changes that have an affect to Kernel. The is the primary reason for the kernel panic. We cannot resize the device without first detaching it from the driver.
対策
Go to the Core console and remove the volume from protection before resizing them.
1. Go to agent on Core and set schedule "not protected' for this device before resizing 2. Press 'refresh metadata' 3. Go to agent run bsctl -l and make sure that device that will be resized not attached 4. resize volume 5. Go to agent on Core and set schedule 'protected ' for this device after resizing 6. Again Press 'refresh metadata'
Note: Step 2 and 6 'refresh metadata' is required for version 6.4 and below. RR-109691
Alternative method: 1. run bsctl -l and make sure that device that will be resized not snapping now 2. run bsctl -d /dev/... for device before resizing (detach device from the driver )
Note: detaching of device should be performed immediately before resizing, because device will be attached to driver automatically during the next scheduled snapshot. 3. resize volume 4. run bsctl -a /dev/...for device after resizing (attach device to the driver )
追加情報
When a new device is created on a protected agent, we automatically attach it to the RR Linux driver. The expected behavior is we should not attach, unless we explicitly protect this device on the core console. RR-109902