Dear , i have one test environment Ceph Firefly 0.80.4, on Debian 7.5 . i do not have enough SSD for each OSD. I want to test speed Ceph perfermance by put journal in a Ramdisk or tmpfs, but when to add new osd use separate disk for OSD data and journal ,it is failure. first , i have test Ram mount to a filesystem and made it to persistent. , i have tested it, it can recovery data from last archive when system boot. >>>>> ramdisk.sh >>>> #! /bin/sh ### BEGIN INIT INFO # Provides: Ramdisk # Required-Start: $remote_fs $syslog # Required-Stop: $remote_fs $syslog # Default-Start: 2 3 4 5 # Default-Stop: 0 1 6 # Short-Description: Ramdisk ### END INIT INFO # /etc/init.d/ramdisk.sh # case "$1" in start) echo "Copying files to ramdisk" cd /mnt mkfs.btrfs /dev/ram0 >> /var/log/ramdisk_sync.log mount /dev/ram0 /mnt/ramdisk/ tar --lzop -xvf ramdisk-backup.tar.lzop >> /var/log/ramdisk_sync.log echo [`date +"%Y-%m-%d %H:%M"`] Ramdisk Synched from HD >> /var/log/ramdisk_s ync.log ;; sync) echo "Synching files from ramdisk to Harddisk" echo [`date +"%Y-%m-%d %H:%M"`] Ramdisk Synched to HD >> /var/log/ramdisk_syn c.log cd /mnt mv -f ramdisk-backup.tar.lzop ramdisk-backup-old.tar.lzop tar --lzop -cvf ramdisk-backup.tar.lzop ramdisk >> /var/log/ramdisk_sync.log ;; stop) echo "Synching logfiles from ramdisk to Harddisk" echo [`date +"%Y-%m-%d %H:%M"`] Ramdisk Synched to HD >> /var/log/ramdisk_syn c.log tar --lzop -cvf ramdisk-backup.tar.lzop ramdisk >> /var/log/ramdisk_sync.log ;; *) echo "Usage: /etc/init.d/ramdisk {start|stop|sync}" exit 1 ;; esac exit 0 ##### then i want to add new OSD use ramdisk for journal. i have tried 3 ways. all failed. 1. ceph-deploy osd --zap-disk --fs-type btrfs create ceph04-vm:/dev/sdb:/dev/ram0 (use device way) 2. ceph-deploy osd prepare ceph04-vm:/mnt/osd:/mnt/ramdisk (use direcotry way) 3. ceph-deploy osd prepare ceph04-vm:/dev/sdb:/mnt/ramdisk could some expert give me some guide on it ??? #### some log##### root at ceph-admin:~/my-cluster# ceph-deploy osd --zap-disk --fs-type btrfs create ceph04-vm:/dev/sdb:/dev/ram0 [ceph_deploy.conf][DEBUG ] found configuration file at: /root/.cephdeploy.conf [ceph_deploy.cli][INFO ] Invoked (1.5.9): /usr/bin/ceph-deploy osd --zap-disk --fs-type btrfs create ceph04-vm:/dev/sdb:/dev/ram0 [ceph_deploy.osd][DEBUG ] Preparing cluster ceph disks ceph04-vm:/dev/sdb:/dev/ram0 [ceph04-vm][DEBUG ] connected to host: ceph04-vm [ceph04-vm][DEBUG ] detect platform information from remote host [ceph04-vm][DEBUG ] detect machine type [ceph_deploy.osd][INFO ] Distro info: debian 7.6 wheezy [ceph_deploy.osd][DEBUG ] Deploying osd to ceph04-vm [ceph04-vm][DEBUG ] write cluster configuration to /etc/ceph/{cluster}.conf [ceph04-vm][INFO ] Running command: udevadm trigger --subsystem-match=block --action=add [ceph_deploy.osd][DEBUG ] Preparing host ceph04-vm disk /dev/sdb journal /dev/ram0 activate True [ceph04-vm][INFO ] Running command: ceph-disk-prepare --zap-disk --fs-type btrfs --cluster ceph -- /dev/sdb /dev/ram0 [ceph04-vm][DEBUG ] **************************************************************************** [ceph04-vm][DEBUG ] Caution: Found protective or hybrid MBR and corrupt GPT. Using GPT, but disk [ceph04-vm][DEBUG ] verification and recovery are STRONGLY recommended. [ceph04-vm][DEBUG ] **************************************************************************** [ceph04-vm][DEBUG ] GPT data structures destroyed! You may now partition the disk using fdisk or [ceph04-vm][DEBUG ] other utilities. [ceph04-vm][DEBUG ] The operation has completed successfully. [ceph04-vm][DEBUG ] Creating new GPT entries. [ceph04-vm][DEBUG ] Information: Moved requested sector from 34 to 2048 in [ceph04-vm][DEBUG ] order to align on 2048-sector boundaries. [ceph04-vm][WARNIN] Caution: invalid backup GPT header, but valid main header; regenerating [ceph04-vm][WARNIN] backup header from main header. [ceph04-vm][WARNIN] [ceph04-vm][WARNIN] WARNING:ceph-disk:OSD will not be hot-swappable if journal is not the same device as the osd data [ceph04-vm][WARNIN] Could not create partition 2 from 34 to 10485793 [ceph04-vm][WARNIN] Unable to set partition 2's name to 'ceph journal'! [ceph04-vm][WARNIN] Could not change partition 2's type code to 45b0969e-9b03-4f30-b4c6-b4b80ceff106! [ceph04-vm][WARNIN] Error encountered; not saving changes. [ceph04-vm][WARNIN] ceph-disk: Error: Command '['/sbin/sgdisk', '--new=2:0:+5120M', '--change-name=2:ceph journal', '--partition-guid=2:ea326680-d389-460d-bef1-3c6bd0ab83c5', '--typecode=2:45b0969e-9b03-4f30-b4c6-b4b80ceff106', '--mbrtogpt', '--', '/dev/ram0']' returned non-zero exit status 4 [ceph04-vm][ERROR ] RuntimeError: command returned non-zero exit status: 1 [ceph_deploy.osd][ERROR ] Failed to execute command: ceph-disk-prepare --zap-disk --fs-type btrfs --cluster ceph -- /dev/sdb /dev/ram0 [ceph_deploy][ERROR ] GenericError: Failed to create 1 OSDs -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.ceph.com/pipermail/ceph-users-ceph.com/attachments/20140731/c28e69a7/attachment.htm>