OK, I managed! I had to add more modules sudo echo "dm_cache" >> /etc/initramfs-tools/modules sudo echo "dm_cache_mq" >> /etc/initramfs-tools/modules sudo echo "dm_persistent_data" >> /etc/initramfs-tools/modules sudo echo "dm_bufio" >> /etc/initramfs-tools/modules
plus, add cache_check as in http://forums.debian.net/viewtopic.php?f=5&t=119644 Booted! This is how I set up the lvmcache sudo vgextend LinuxVG /dev/sdb2 sudo lvcreate -L 10G -n rootCacheLV LinuxVG /dev/sdb2 sudo lvcreate -L 24M -n rootCacheMetaLV LinuxVG /dev/sdb2 sudo lvcreate -L 10G -n homeCacheLV LinuxVG /dev/sdb2 sudo lvcreate -L 24M -n homeCacheMetaLV LinuxVG /dev/sdb2 sudo lvconvert --type cache-pool --poolmetadata LinuxVG/rootCacheMetaLV --cachemode writethrough LinuxVG/rootCacheLV sudo lvconvert --type cache-pool --poolmetadata LinuxVG/homeCacheMetaLV --cachemode writethrough LinuxVG/homeCacheLV sudo lvconvert --type cache --cachepool LinuxVG/rootCacheLV LinuxVG/rootLV sudo lvconvert --type cache --cachepool LinuxVG/homeCacheLV LinuxVG/homeLV where LinuxVG has the root at rootLV and home at homeLV and sdb2 is an SSD -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1423796 Title: Unable to mount lvmcache root device at boot time Status in initramfs-tools package in Ubuntu: Confirmed Status in linux package in Ubuntu: Confirmed Status in lvm2 package in Ubuntu: Confirmed Bug description: I'm experimenting with Vivid Vervet on a virtual machine and tried a new LVM feature, lvmcache. I made a cache for the root file system, rebuilt the initrd and rebooted the VM. At boot time, the system failed to activate the root LV. After some investigation, I found out, it's because the initrd is missing some essential stuff needed for activating a cached LV. The initrd was missing the dm-cache module. I regenerated the initrd with explicitly listing dm-cache in /etc/initramfs-tools/modules, but the system still can't boot up, because now it is missing the /usr/sbin/cache_check utility. As SSDs are becoming more and more common, I think it will be common to use them as cache for root file systems, thus it is mandatory to make sure that an initrd can mount an lvmcached root device when necessary, preferably without /etc/initramfs-tools/modules and other manual initrd hacking. System details: Linux lvmvm 3.18.0-13-generic #14-Ubuntu SMP Fri Feb 6 09:55:14 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux Distributor ID: Ubuntu Description: Ubuntu Vivid Vervet (development branch) Release: 15.04 Codename: vivid LVM version: 2.02.111(2) (2014-09-01) Library version: 1.02.90 (2014-09-01) Driver version: 4.28.0 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/initramfs-tools/+bug/1423796/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
