Paul Koch
2015-Jun-22 05:41 UTC
bootonce not set in backup partition table - virtualbox guest with SAS controller
We seem to have a problem where after setting bootonce on an alternate root
partition, the backup partition table does not match the primary after
rebooting onto an alternate root.
Setup:
- 10.1-RELEASE-p12 host
- VirtualBox 4.3.28
- 10.1-RELEASE-p12 guest, SAS controller with 50G fixed sized disk.
This problem does not happen when we setup the guest with a 50G fixed disk
off a SATA controller.
We have an custom install setup where we create two 5G root partitions,
/ and /alt. This allows us to install a new OS+packages onto the alt,
set bootonce and reboot using /alt.
After our initial install we have:
# diskinfo -v da0
da0
512 # sectorsize
53687091200 # mediasize in bytes (50G)
104857600 # mediasize in sectors
0 # stripesize
0 # stripeoffset
6527 # Cylinders according to firmware.
255 # Heads according to firmware.
63 # Sectors according to firmware.
# Disk ident.
# gpart show
=> 34 104857533 da0 GPT (50G)
34 6 - free - (3.0K)
40 1024 1 freebsd-boot (512K)
1064 8388608 2 freebsd-swap (4.0G)
8389672 984 - free - (492K)
8390656 10485760 3 freebsd-ufs [bootme] (5.0G)
18876416 10485760 4 freebsd-ufs (5.0G)
29362176 75493376 5 freebsd-zfs (36G)
104855552 2015 - free - (1.0M)
# gpart status
Name Status Components
da0p1 OK da0
da0p2 OK da0
da0p3 OK da0
da0p4 OK da0
da0p5 OK da0
MD5 of the primary and backup partition tables are identical.
# dd if=/dev/da0 bs=512 skip=2 count=32 2>/dev/null | md5
03fb4d3642e76f454c5649e96512bd6f
# dd if=/dev/da0 bs=512 skip=104857567 count=32 2>/dev/null | md5
03fb4d3642e76f454c5649e96512bd6f
We then do an upgrade where we install onto /alt and set the appropriate
bootonce flag using
gpart set -a bootonce -i 4 da0
After it boots on the alternate root:
# diskinfo -v da0
da0
512 # sectorsize
53687091200 # mediasize in bytes (50G)
104857600 # mediasize in sectors
0 # stripesize
0 # stripeoffset
6527 # Cylinders according to firmware.
255 # Heads according to firmware.
63 # Sectors according to firmware.
# Disk ident.
# gpart show
=> 34 104857533 da0 GPT (50G) [CORRUPT]
34 6 - free - (3.0K)
40 1024 1 freebsd-boot (512K)
1064 8388608 2 freebsd-swap (4.0G)
8389672 984 - free - (492K)
8390656 10485760 3 freebsd-ufs [bootme] (5.0G)
18876416 10485760 4 freebsd-ufs [bootonce] (5.0G)
29362176 75493376 5 freebsd-zfs (36G)
104855552 2015 - free - (1.0M)
# gpart status
Name Status Components
da0p1 CORRUPT da0
da0p2 CORRUPT da0
da0p3 CORRUPT da0
da0p4 CORRUPT da0
da0p5 CORRUPT da0
Dump of the primary GPT header
# dd if=/dev/da0 bs=512 skip=1 count=1 2>/dev/null | hexdump
0000000 4645 2049 4150 5452 0000 0001 005c 0000
0000010 11e9 ae86 0000 0000 0001 0000 0000 0000
0000020 ffff 063f 0000 0000 0022 0000 0000 0000
0000030 ffde 063f 0000 0000 378d 9abb 18ed 11e5
0000040 9e8d 0008 3f27 7893 0002 0000 0000 0000
0000050 0080 0000 0080 0000 b6fe fca6 0000 0000
0000060 0000 0000 0000 0000 0000 0000 0000 0000
*
Dump of the backup GPT header
# dd if=/dev/da0 bs=512 skip=104857599 count=1 2>/dev/null | hexdump
0000000 4645 2049 4150 5452 0000 0001 005c 0000
0000010 2997 eaf5 0000 0000 ffff 063f 0000 0000
0000020 0001 0000 0000 0000 0022 0000 0000 0000
0000030 ffde 063f 0000 0000 378d 9abb 18ed 11e5
0000040 9e8d 0008 3f27 7893 ffdf 063f 0000 0000
0000050 0080 0000 0080 0000 d0ab 529c 0000 0000
0000060 0000 0000 0000 0000 0000 0000 0000 0000
*
MD5 of the primary and backup partition tables are different.
# dd if=/dev/da0 bs=512 skip=2 count=32 2>/dev/null | md5
1e8cc33d84d2ae1ec7621a662ac8cca0
# dd if=/dev/da0 bs=512 skip=104857567 count=32 2>/dev/null | md5
f07e707260e734d4a9d5baeaa077bc58
Dump of the primary partition table
# dd if=/dev/da0 bs=512 skip=2 count=32 2>/dev/null | hexdump
0000000 6b9d 83bd 7f41 11dc 0bbe 1500 b860 0f4f
0000010 b409 9abc 18ed 11e5 9e8d 0008 3f27 7893
0000020 0028 0000 0000 0000 0427 0000 0000 0000
0000030 0000 0000 0000 0000 0067 0070 0074 0062
0000040 006f 006f 0074 0000 0000 0000 0000 0000
0000050 0000 0000 0000 0000 0000 0000 0000 0000
*
0000080 7cb5 516e 6ecf 11d6 f88f 0200 092d 2b71
0000090 3b28 9abe 18ed 11e5 9e8d 0008 3f27 7893
00000a0 0428 0000 0000 0000 0427 0080 0000 0000
00000b0 0000 0000 0000 0000 0061 006b 0069 0070
00000c0 0073 002d 0073 0077 0061 0070 0000 0000
00000d0 0000 0000 0000 0000 0000 0000 0000 0000
*
0000100 7cb6 516e 6ecf 11d6 f88f 0200 092d 2b71
0000110 c0b3 9abf 18ed 11e5 9e8d 0008 3f27 7893
0000120 0800 0080 0000 0000 07ff 0120 0000 0000
0000130 0000 0000 0000 0800 0061 006b 0069 0070
0000140 0073 002d 0072 006f 006f 0074 0030 0000
0000150 0000 0000 0000 0000 0000 0000 0000 0000
*
0000180 7cb6 516e 6ecf 11d6 f88f 0200 092d 2b71
0000190 66da 9ac1 18ed 11e5 9e8d 0008 3f27 7893
00001a0 0800 0120 0000 0000 07ff 01c0 0000 0000
00001b0 0000 0000 0000 0400 0061 006b 0069 0070
00001c0 0073 002d 0072 006f 006f 0074 0031 0000
00001d0 0000 0000 0000 0000 0000 0000 0000 0000
*
0000200 7cba 516e 6ecf 11d6 f88f 0200 092d 2b71
0000210 1d30 9ac3 18ed 11e5 9e8d 0008 3f27 7893
0000220 0800 01c0 0000 0000 f7ff 063f 0000 0000
0000230 0000 0000 0000 0000 0061 006b 0069 0070
0000240 0073 002d 0068 006f 006d 0065 0000 0000
0000250 0000 0000 0000 0000 0000 0000 0000 0000
*
Dump of the backup partition table
# dd if=/dev/da0 bs=512 skip=104857567 count=32 2>/dev/null | hexdump
0000000 6b9d 83bd 7f41 11dc 0bbe 1500 b860 0f4f
0000010 b409 9abc 18ed 11e5 9e8d 0008 3f27 7893
0000020 0028 0000 0000 0000 0427 0000 0000 0000
0000030 0000 0000 0000 0000 0067 0070 0074 0062
0000040 006f 006f 0074 0000 0000 0000 0000 0000
0000050 0000 0000 0000 0000 0000 0000 0000 0000
*
0000080 7cb5 516e 6ecf 11d6 f88f 0200 092d 2b71
0000090 3b28 9abe 18ed 11e5 9e8d 0008 3f27 7893
00000a0 0428 0000 0000 0000 0427 0080 0000 0000
00000b0 0000 0000 0000 0000 0061 006b 0069 0070
00000c0 0073 002d 0073 0077 0061 0070 0000 0000
00000d0 0000 0000 0000 0000 0000 0000 0000 0000
*
0000100 7cb6 516e 6ecf 11d6 f88f 0200 092d 2b71
0000110 c0b3 9abf 18ed 11e5 9e8d 0008 3f27 7893
0000120 0800 0080 0000 0000 07ff 0120 0000 0000
0000130 0000 0000 0000 0800 0061 006b 0069 0070
0000140 0073 002d 0072 006f 006f 0074 0030 0000
0000150 0000 0000 0000 0000 0000 0000 0000 0000
*
0000180 7cb6 516e 6ecf 11d6 f88f 0200 092d 2b71
0000190 66da 9ac1 18ed 11e5 9e8d 0008 3f27 7893
00001a0 0800 0120 0000 0000 07ff 01c0 0000 0000
00001b0 0000 0000 0000 0c00 0061 006b 0069 0070 <<< different
00001c0 0073 002d 0072 006f 006f 0074 0031 0000
00001d0 0000 0000 0000 0000 0000 0000 0000 0000
*
0000200 7cba 516e 6ecf 11d6 f88f 0200 092d 2b71
0000210 1d30 9ac3 18ed 11e5 9e8d 0008 3f27 7893
0000220 0800 01c0 0000 0000 f7ff 063f 0000 0000
0000230 0000 0000 0000 0000 0061 006b 0069 0070
0000240 0073 002d 0068 006f 006d 0065 0000 0000
0000250 0000 0000 0000 0000 0000 0000 0000 0000
*
The line at offset 00001b0 is out by one bit. Looks like the bootonce
flag is only updated in the primary partition table and not the backup.
At this point our boot script tries to do
gpart set -a bootme -i 4 da0
gpart unset -a bootme -i 3 da0
gpart unset -a bootonce -i 4 da0
but we of course get
gpart: table 'da0' is corrupt: Operation not permitted
We currently have a workaround that does
gpart recover da0
before doing the set/unset gpart commands.
Not sure what we are doing wrong because it all works fine if we configure
the vm guest using a SATA controller.
Paul.
--
Paul Koch | Founder, CEO
AKIPS Network Monitor | akips.com
Brisbane, Australia