為什麼“aptitude safe-upgrade”會導致 Ubuntu 的啟動掛在“等待根文件系統”？

我使用 Ubuntu 自己的最新 AMI 10.04 Lucid，ami-ad36fbc4在 Amazon EC2 上啟動了一個 Ubuntu EBS 實例

啟動實例後，我執行了sudo aptitude safe-upgrade似乎已將核心從升級到vmlinuz-2.6.32-318-ec2的命令vmlinuz-2.6.32-340-ec2

現在實例無法啟動，它給出以下錯誤：Waiting for root file system ...

如果我分離 EBS 並編輯/boot/grub/menu.lst文件並刪除引用vmlinuz-2.6.32-340-ec2它的條目將再次啟動。

所以問題是：

1. 為什麼會這樣？
2. 不safe-upgrade應該保守到不破壞事物的地步嗎？
3. 還是我不應該在 EC2 實例上使用安全升級？如果是這樣，為什麼不呢？

ps：我在研究這個問題時讀到的一個相關問題是系統啟動掛起等待根文件系統 - 從變成 /dev/sda 的 /dev/hda 恢復的過程（參見第 4.8 節），但從menu.lst條目由LABEL=cloudimg-rootfs和 不引用/sda/a和/hda/a

作為參考，grub 菜單文件如下：

title       Ubuntu 10.04.3 LTS, kernel 2.6.32-340-ec2
root        (hd0)
kernel      /boot/vmlinuz-2.6.32-340-ec2 root=LABEL=cloudimg-rootfs ro xencons=hvc0 console=hvc0 
initrd      /boot/initrd.img-2.6.32-340-ec2

title       Ubuntu 10.04.3 LTS, kernel 2.6.32-340-ec2 (recovery mode)
root        (hd0)
kernel      /boot/vmlinuz-2.6.32-340-ec2 root=LABEL=cloudimg-rootfs ro  single
initrd      /boot/initrd.img-2.6.32-340-ec2

title       Ubuntu 10.04.3 LTS, kernel 2.6.32-318-ec2
root        (hd0)
kernel      /boot/vmlinuz-2.6.32-318-ec2 root=LABEL=cloudimg-rootfs ro xencons=hvc0 console=hvc0 
initrd      /boot/initrd.img-2.6.32-318-ec2

title       Ubuntu 10.04.3 LTS, kernel 2.6.32-318-ec2 (recovery mode)
root        (hd0)
kernel      /boot/vmlinuz-2.6.32-318-ec2 root=LABEL=cloudimg-rootfs ro  single
initrd      /boot/initrd.img-2.6.32-318-ec2

title       Ubuntu 10.04.3 LTS, memtest86+
root        (hd0)
kernel      /boot/memtest86+.bin

引導控制台看起來像這樣（當它掛起時）：

i-3121e5b7
2011-11-27T19:20:03+0000
Xen Minimal OS!
 start_info: 0xac4000(VA)
   nr_pages: 0x26700
 shared_inf: 0xbb4b2000(MA)
    pt_base: 0xac7000(VA)
nr_pt_frames: 0x9
   mfn_list: 0x990000(VA)
  mod_start: 0x0(VA)
    mod_len: 0
      flags: 0x0
   cmd_line: root=/dev/sda1 ro 4
 stack:      0x94f860-0x96f860
MM: Init
     _text: 0x0(VA)
    _etext: 0x5ff6d(VA)
  _erodata: 0x78000(VA)
    _edata: 0x80b00(VA)
stack start: 0x94f860(VA)
      _end: 0x98fe68(VA)
 start_pfn: ad3
   max_pfn: 26700
Mapping memory range 0xc00000 - 0x26700000
setting 0x0-0x78000 readonly
skipped 0x1000
MM: Initialise page allocator for c01000(c01000)-26700000(26700000)
MM: done
Demand map pfns at 26701000-2026701000.
Heap resides at 2026702000-4026702000.
Initialising timer interface
Initialising console ... done.
gnttab_table mapped at 0x26701000.
Initialising scheduler
Thread "Idle": pointer: 0x2026702010, stack: 0x26640000
Initialising xenbus
Thread "xenstore": pointer: 0x20267027c0, stack: 0x26650000
Dummy main: start_info=0x96f960
Thread "main": pointer: 0x2026702f70, stack: 0x26660000
"main" "root=/dev/sda1" "ro" "4" 
vbd 2049 is hd0
******************* BLKFRONT for device/vbd/2049 **********


backend at /local/domain/0/backend/vbd/526/2049
Failed to read /local/domain/0/backend/vbd/526/2049/feature-barrier.
Failed to read /local/domain/0/backend/vbd/526/2049/feature-flush-cache.
16777216 sectors of 512 bytes
**************************
[H[J  Booting 'Ubuntu 10.04.3 LTS, kernel 2.6.32-340-ec2'

root  (hd0)
Filesystem type is ext2fs, using whole disk
kernel  /boot/vmlinuz-2.6.32-340-ec2 root=LABEL=cloudimg-rootfs ro xencons=hvc0
console=hvc0 
initrd  /boot/initrd.img-2.6.32-340-ec2

xc_dom_probe_bzimage_kernel: kernel is not a bzImage
close blk: backend at /local/domain/0/backend/vbd/526/2049
[    0.000000] Initializing cgroup subsys cpuset
[    0.000000] Initializing cgroup subsys cpu
[    0.000000] Linux version 2.6.32-340-ec2 (buildd@yellow) (gcc version 4.4.3 (Ubuntu 4.4.3-4ubuntu5) ) #40-Ubuntu SMP Wed Nov 16 14:36:38 UTC 2011 (Ubuntu 2.6.32-340.40-ec2 2.6.32.46+drm33.20)
[    0.000000] Command line: root=LABEL=cloudimg-rootfs ro xencons=hvc0 console=hvc0 
[    0.000000] KERNEL supported cpus:
[    0.000000]   Intel GenuineIntel
[    0.000000]   AMD AuthenticAMD
[    0.000000]   Centaur CentaurHauls
[    0.000000] Xen-provided physical RAM map:
[    0.000000]  Xen: 0000000000000000 - 0000000026f00000 (usable)
[    0.000000] last_pfn = 0x26f00 max_arch_pfn = 0x80000000
[    0.000000] init_memory_mapping: 0000000000000000-0000000026f00000
[    0.000000] NX (Execute Disable) protection: active
[    0.000000] RAMDISK: 01844000 - 03293000
[    0.000000] (3 early reservations) ==> bootmem [0000000000 - 0026700000]
[    0.000000]   #0 [0001844000 - 00033e9000]     Xen provided ==> [0001844000 - 00033e9000]
[    0.000000]   #1 [0001000000 - 00018237b8]    TEXT DATA BSS ==> [0001000000 - 00018237b8]
[    0.000000]   #2 [00033e9000 - 0003523000]          PGTABLE ==> [00033e9000 - 0003523000]
[    0.000000] Zone PFN ranges:
[    0.000000]   DMA      0x00000000 -> 0x00001000
[    0.000000]   DMA32    0x00001000 -> 0x00100000
[    0.000000]   Normal   0x00100000 -> 0x00100000
[    0.000000] Movable zone start PFN for each node
[    0.000000] early_node_map[2] active PFN ranges
[    0.000000]     0: 0x00000000 -> 0x00026700
[    0.000000]     0: 0x00026f00 -> 0x00026f00
[    0.000000] NR_CPUS:64 nr_cpumask_bits:64 nr_cpu_ids:1 nr_node_ids:1
[    0.000000] PERCPU: Embedded 18 pages/cpu @ffff880003298000 s44248 r8192 d21288 u73728
[    0.000000] pcpu-alloc: s44248 r8192 d21288 u73728 alloc=18*4096
[    0.000000] pcpu-alloc: [0] 0 
[    0.000000] Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 155259
[    0.000000] Kernel command line: root=LABEL=cloudimg-rootfs ro xencons=hvc0 console=hvc0 
[    0.000000] PID hash table entries: 4096 (order: 3, 32768 bytes)
[    0.000000] Dentry cache hash table entries: 131072 (order: 8, 1048576 bytes)
[    0.000000] Inode-cache hash table entries: 65536 (order: 7, 524288 bytes)
[    0.000000] Initializing CPU#0
[    0.000000] allocated 6379520 bytes of page_cgroup
[    0.000000] please try 'cgroup_disable=memory' option if you don't want memory cgroups
[    0.000000] Software IO TLB disabled
[    0.000000] Memory: 574464k/637952k available (4836k kernel code, 8192k absent, 54588k reserved, 2084k data, 228k init)
[    0.000000] Hierarchical RCU implementation.
[    0.000000] NR_IRQS:96
[    0.000000] Xen reported: 2666.760 MHz processor.
[    0.000000] Console: colour dummy device 80x25
[    0.000000] console [hvc0] enabled
[    0.230003] Calibrating delay using timer specific routine.. 5347.09 BogoMIPS (lpj=26735464)
[    0.230055] Security Framework initialized
[    0.230073] AppArmor: AppArmor initialized
[    0.230089] Mount-cache hash table entries: 256
[    0.230209] Initializing cgroup subsys ns
[    0.230215] Initializing cgroup subsys cpuacct
[    0.230218] Initializing cgroup subsys memory
[    0.230228] Initializing cgroup subsys devices
[    0.230230] Initializing cgroup subsys freezer
[    0.230259] CPU: L1 I cache: 32K, L1 D cache: 32K
[    0.230262] CPU: L2 cache: 6144K
[    0.230271] SMP alternatives: switching to UP code
[    0.255645] Freeing SMP alternatives: 39k freed
[    0.255834] Brought up 1 CPUs
[    0.255922] devtmpfs: initialized
[    0.256333] NET: Registered protocol family 16
[    0.256945] Brought up 1 CPUs
[    0.257349] PCI: Fatal: No config space access function found
[    0.257353] PCI: setting up Xen PCI frontend stub
[    0.257605] bio: create slab <bio-0> at 0
[    0.257681] vgaarb: loaded
[    0.257889] suspend: event channel 9
[    0.258172] xen_mem: Initialising balloon driver.
[    0.260364] PCI: System does not support PCI
[    0.260368] PCI: System does not support PCI
[    0.260432] NET: Registered protocol family 8
[    0.260435] NET: Registered protocol family 20
[    0.260451] NetLabel: Initializing
[    0.260455] NetLabel:  domain hash size = 128
[    0.260456] NetLabel:  protocols = UNLABELED CIPSOv4
[    0.260490] NetLabel:  unlabeled traffic allowed by default
[    0.260505] Switching to clocksource xen
[    0.261840] AppArmor: AppArmor Filesystem Enabled
[    0.262007] NET: Registered protocol family 2
[    0.262083] IP route cache hash table entries: 32768 (order: 6, 262144 bytes)
[    0.262363] TCP established hash table entries: 131072 (order: 9, 2097152 bytes)
[    0.263136] TCP bind hash table entries: 65536 (order: 8, 1048576 bytes)
[    0.263553] TCP: Hash tables configured (established 131072 bind 65536)
[    0.263559] TCP reno registered
[    0.263629] NET: Registered protocol family 1
[    0.263708] platform rtc_cmos: registered platform RTC device (no PNP device found)
[    0.263814] audit: initializing netlink socket (disabled)
[    0.263838] type=2000 audit(1322421419.386:1): initialized
[    0.269569] Trying to unpack rootfs image as initramfs...
[    0.279699] VFS: Disk quotas dquot_6.5.2
[    0.279731] Dquot-cache hash table entries: 512 (order 0, 4096 bytes)
[    0.279885] DLM (built Nov 16 2011 14:40:41) installed
[    0.279994] JFS: nTxBlock = 4920, nTxLock = 39360
[    0.289416] SGI XFS with ACLs, security attributes, realtime, large block/inode numbers, no debug enabled
[    0.289643] SGI XFS Quota Management subsystem
[    0.299611] Slow work thread pool: Starting up
[    0.299651] Slow work thread pool: Ready
[    0.299659] GFS2 (built Nov 16 2011 14:41:38) installed
[    0.299675] msgmni has been set to 1230
[    0.299847] alg: No test for stdrng (krng)
[    0.299858] io scheduler noop registered
[    0.299860] io scheduler anticipatory registered
[    0.299862] io scheduler deadline registered (default)
[    0.299871] io scheduler cfq registered
[    0.314987] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
[    0.315818] brd: module loaded
[    0.316148] loop: module loaded
[    0.316216] Xen virtual console successfully installed as hvc0
[    0.316254] Event-channel device installed.
[    0.324444] Freeing initrd memory: 26940k freed
[    0.338978] netfront: Initialising virtual ethernet driver.
[    0.340057] PPP generic driver version 2.4.2
[    0.340628] Equalizer2002: Simon Janes (simon@ncm.com) and David S. Miller (davem@redhat.com)
[    0.340767] tun: Universal TUN/TAP device driver, 1.6
[    0.340769] tun: (C) 1999-2004 Max Krasnyansky <maxk@qualcomm.com>
[    0.341644] i8042.c: No controller found.
[    0.341704] mice: PS/2 mouse device common for all mice
[    0.341758] rtc_cmos rtc_cmos: rtc core: registered rtc_cmos as rtc0
[    0.341810] Driver for 1-wire Dallas network protocol.
[    0.341865] device-mapper: uevent: version 1.0.3
[    0.341932] device-mapper: ioctl: 4.15.0-ioctl (2009-04-01) initialised: dm-devel@redhat.com
[    0.342186] NET: Registered protocol family 17
[    0.342285] registered taskstats version 1
[    0.355601] xen-vbd: registered block device major 8
[    0.440415] XENBUS: Device with no driver: device/console/0
[    0.440429] /build/buildd/linux-ec2-2.6.32/drivers/rtc/hctosys.c: unable to open rtc device (rtc0)
[    0.440534] Freeing unused kernel memory: 228k freed
[    0.440675] Write protecting the kernel read-only data: 6492k
Loading, please wait...
[    0.460565] udev: starting version 151
Begin: Loading essential drivers ... done.
Begin: Running /scripts/init-premount ... done.
Begin: Mounting root file system ... Begin: Running /scripts/local-top ... done.
Begin: Waiting for root file system ... 

很抱歉，這個回复太遲了。先評論幾句：

• 將來，如果您發現在 Amazon 的 EC2 上執行的 Ubuntu 存在問題，解決問題的最佳方法是在啟動板 ( http://launchpad.net/ubuntu ) 中打開一個錯誤。您可以在 EC2 實例中執行“ubuntu-bug”，它會收集有關該實例的一些資訊並適當地標記錯誤。此外，請隨時訂閱“smoser”或“utlemming”。
• 您列出的 ami 不再是最新的（僅僅是由於時間的流逝，以及 Ubuntu 在 EC2 上刷新圖像）。如果您有興趣查找最新的官方 AMI，請參閱

   https://askubuntu.com/questions/53582/how-do-i-know-what-ubuntu-ami-to-launch-on-ec2

• 您執行的核心不再是 10.04 的最新版本（同樣，僅僅是由於 Ubuntu 上的維護）。

所以，綜上所述，aptitude safe-upgrade在 EC2 上執行應該是安全的。我驗證了在 t1.micro 和 m1.large 上使用上面列出的 AMI 時這樣做是有效的。在這個時間點，這導致核心“2.6.32-341.42”而不是你得到的“2.6.32-340.40”。

我試圖通過啟動板存檔下載和安裝相同版本的核心來明確重現您的問題。我的 t1.micro 和 m1.large 實例在簡單的sudo dpkg -i linux-image-2.6.32-340-ec2_2.6.32-340.40_amd64.deb && sudo reboot.

同樣，在 EC2aptitude safe-upgrade上apt-get dist-upgrade應該是完全安全的。如果不是，請打開錯誤。

引用自：https://serverfault.com/questions/335237