Hi! Recently I have installed Debian 8 (jessie) on a HP ProLiant DL360 G4 server (2 x Xeon 3 GHz; RAM 3 GiB ECC DDR 333 MHz; HP Smart Array 6i; RAID1 72 GB with 2 x 72 GB SCSI Ultra 320 HDD). For some reasons upgrade to Debian 9 is not an option at the moment.
$ uname -a Linux myserver 3.16.0-4-amd64 #1 SMP Debian 3.16.43-2+deb8u2 (2017-06-26) x86_64 GNU/Linux After a day or two of uptime the system freezes (network services not working, users cannot login). On the console I can see kernel messages as the following: INFO: task jbd2/cciss!c0d0:297 blocked for more than 120 seconds Not tainted 3.16.0-4-amd64 #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. INFO: task jbd2/cciss!c0d0:301 blocked for more than 120 seconds Not tainted 3.16.0-4-amd64 #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. The messages repeat a couple of times every 120 sec. Sometimes the messages also mention other tasks, e.g. kworker, apache2. As suggested on https://www.blackmoreops.com/2014/09/22/linux-kernel-panic-issue-fix-hung_task_timeout_secs-blocked-120-seconds-problem/ I tried to add the following in /etc/sysctl.conf vm.dirty_background_ratio = 5 vm.dirty_ratio = 10 but to no avail. Memory test did not find any problem with RAM. Testing partitions with "fsck.ext2 -f -cc" did not show any problems either. I tried to install newer kernel from jessie-backports: $ sudo apt install -t jessie-backports linux-image-amd64 ... The following extra packages will be installed: linux-base linux-image-4.9.0-0.bpo.3-amd64 ... but then booting stops at "Loading initial ramdisk". Could someone give any advice on this issue, please? -- rpr.