Public bug reported: Binary package hint: multipath-tools-boot
After installing "multipath-tools-boot", initramfs fails to mount /root by uuid with error: "failed: Device or resource busy". And boot process falls into (initramfs) prompt. **Boot/Screen Output:** Begin: Running /scripts/local-premount ... done. mount: mounting /dev/disk/by-uuid/082f71b9-47dc-4d4b-bdfa-d5ca61f1e045 on /root failed: Device or resource busy Begin: Running /scripts/local-bottom ... done. done. <....> other failure messages mounting (dev, sys, proc, etc.) <....> (initramfs) **Further Debugging & Info:** Procedures & commands, run shortly after (initramfs) prompt appears. (initramfs) ls -l /dev/disk/by-uuid/ lrwxrwxrwx 1 10 082f71b9-47dc-4d4b-bdfa-d5ca61f1e045 -> ../../dm1 [ This appears correct!?! ] (initramfs) mount /dev/disk/by-uuid/082f71b9-47dc-4d4b-bdfa-d5ca61f1e045 /root [ SUCCESS ! ] **WORKAROUND:** I have created an initramfs script to slow-down the root mounting attempt: File: /usr/share/initramfs-tools/scripts/local-top/waitfor-multipath Content: #!/bin/sh VERBOSITY=0 PREREQ="multipath" prereqs() { echo "$PREREQ"; } case $1 in prereqs) prereqs exit 0 ;; esac echo "Waiting 5 seconds for multipaths & udev?? to settle down..." sleep 5 exit 0 <----END----> My guess for a general/global bug-fix is multipath-tools-boot script to include a slight delay/hold-down timer; to allow outside device-mapping procedures to complete. ..or a confirmation that dm devices have finished mapping. **Observations:** It appears multipath-tools-boot initramfs script executes successfully VERY quickly, and initramfs scripts continue with attempting to mount the root file system. Although, dm-# /dev/disk/by-uuid mappings are not instantly ready. This is why manually typing the same mount command at prompt is immediately successful. _To duplicate error in a non-boot scenario:_ This exact same behavior can be observed & duplicated on running servers; when mounting a multipath (SAN) volume. As example; mounting multipath-SAN targets will create: /dev/sda, /dev/sdb, /dev/sdc, etc.... And multipath-tools+devmapper will then create the shared/linked /dev/dm-# mappings. You are then only supposed to use the /dev/dm-# virtual devices to access multipathed SAN devices (multipaths.) .... If you then attempt to mount a direct SAN volume /dev/sd?# an error is raised: "mount: /dev/sd?# already mounted or /<mount_point> busy" **Software & Versions:** OS: Ubuntu 10.10 (Maverick - server) Related Packages & versions: multipath-tools 0.4.8-14ubuntu4 multipath-tools-boot 0.4.8-14ubuntu4 udev 162-2.1 initramfs-tools 0.98.1ubuntu6 initramfs-tools-bin 0.98.1ubuntu6 open-iscsi 2.0.871-0ubuntu5 open-iscsi-utils 2.0.871-0ubuntu5 libdevmapper1.02.1 2:1.02.39-1ubuntu6 **Hardware Details:** Servers affected: HP Proliant DL385 (G5, G5p, G6) (and others I'm sure.) Storage/SAN Type: iSCSI Storage/SAN Hardware: HP StorageWorks MSA2312i (and others I'm sure.) This problem affects servers with iSCSI-boot NICs, AND servers which have a USB-Key with /boot partition. Please let me know if more information is necessary! ** Affects: multipath-tools (Ubuntu) Importance: Undecided Status: New ** Tags: by-uuid initramfs iscsi multipath multipath-tools-boot san -- You received this bug notification because you are a member of Ubuntu Server Team, which is subscribed to multipath-tools in ubuntu. https://bugs.launchpad.net/bugs/686832 Title: multipath-tools-boot, root mount failed - Device or resource busy -- Ubuntu-server-bugs mailing list Ubuntu-server-bugs@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-server-bugs