Arch Linux

xhemi

Member

From: /dev/urandom

Registered: 2007-03-14

Posts: 11

Website

[SOLVED] /dev/md0 as the rootfs blockdevice

hello everybody!
im trying for the first time to use a raid1 block device for my root filesystem.

[root@nexus ]# fdisk -l /dev/sd{a,b}

Disk /dev/sda: 500.1 GB, 500107862016 bytes
2 heads, 4 sectors/track, 122096646 cylinders
Units = cylinders of 8 * 512 = 4096 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1              17   122096646   488386520   83  Linux

Disk /dev/sdb: 500.1 GB, 500107862016 bytes
2 heads, 4 sectors/track, 122096646 cylinders
Units = cylinders of 8 * 512 = 4096 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1              17   122096646   488386520   83  Linux

[root@nexus ]# mdadm --misc --detail /dev/md0
/dev/md0:
        Version : 00.90.03
  Creation Time : Wed Sep 26 21:43:35 2007
     Raid Level : raid1
     Array Size : 488386432 (465.76 GiB 500.11 GB)
  Used Dev Size : 488386432 (465.76 GiB 500.11 GB)
   Raid Devices : 2
  Total Devices : 2
Preferred Minor : 0
    Persistence : Superblock is persistent

    Update Time : Tue Oct  2 09:10:32 2007
          State : clean
 Active Devices : 2
Working Devices : 2
 Failed Devices : 0
  Spare Devices : 0

           UUID : 074fc124:243be3e7:35be5755:bc6991cd
         Events : 0.6

    Number   Major   Minor   RaidDevice State
       0       8        1        0      active sync   /dev/sda1
       1       8       17        1      active sync   /dev/sdb1

which seems fine by me and the system boots.

my fstab:

[root@nexus ]# grep ^[^#] /etc/fstab
/dev/md0        /       reiserfs        rw,suid,dev,exec,auto,nouser,sync 0 1 
/swap1          none    swap            sw 1 0
none                   /dev/pts      devpts    defaults            0      0
none                   /dev/shm      tmpfs     defaults            0      0
/dev/cdrom             /mnt/cd   iso9660   ro,user,noauto,unhide   0      0
/dev/dvd               /mnt/dvd  udf       ro,user,noauto,unhide   0      0
/dev/fd0               /mnt/fl   vfat      user,noauto             0      0

the problem is that file permissions are honored in an inconsistent manner. as an example:

[root@nexus ]# sudo -u mysql ls /
sudo: can't open /etc/sudoers: Permission denied

i.e. root cannot access /etc/sudoers..

another example:

[root@nexus ]# ls -aFlhd /var/lib/mysql/
drwxrwxr-x 11 mysql mysql 392 2007-10-02 09:15 /var/lib/mysql//

[root@nexus ]# mysqld_safe
nohup: ignoring input and redirecting stderr to stdout
Starting mysqld daemon with databases from /var/lib/mysql
STOPPING server from pid file /var/run/mysqld/mysqld.pid
071002 09:15:50  mysqld ended

[root@nexus ]# grep ^[^#] /etc/my.cnf 
[client]
port                                            = 3306
socket                                          = /var/run/mysqld/mysqld.sock
[mysql]
character-sets-dir=/usr/share/mysql/charsets
default-character-set=utf8
[mysqladmin]
character-sets-dir=/usr/share/mysql/charsets
default-character-set=utf8
[mysqlcheck]
character-sets-dir=/usr/share/mysql/charsets
default-character-set=utf8
[mysqldump]
character-sets-dir=/usr/share/mysql/charsets
default-character-set=utf8
[mysqlimport]
character-sets-dir=/usr/share/mysql/charsets
default-character-set=utf8
[mysqlshow]
character-sets-dir=/usr/share/mysql/charsets
default-character-set=utf8
[myisamchk]
character-sets-dir=/usr/share/mysql/charsets
[myisampack]
character-sets-dir=/usr/share/mysql/charsets
[mysqld_safe]
err-log                                         = /var/log/mysql/mysql.err
[mysqld]
character-set-server            = utf8
default-character-set           = utf8
user                                            = mysql
port                                            = 3306
socket                                          = /var/run/mysqld/mysqld.sock
pid-file                                        = /var/run/mysqld/mysqld.pid
log-error                                       = /var/log/mysql/mysqld.err
basedir                                         = /usr
datadir                                         = /var/lib/mysql
skip-locking
key_buffer                                      = 16M
max_allowed_packet                      = 1M
table_cache                             = 64
sort_buffer_size                        = 512K
net_buffer_length                       = 8K
read_buffer_size                        = 256K
read_rnd_buffer_size            = 512K
myisam_sort_buffer_size         = 8M
language                                        = /usr/share/mysql/english
bind-address                            = localhost
server-id                                       = 1
tmpdir                                          = /tmp/
innodb_buffer_pool_size = 16M
innodb_additional_mem_pool_size = 2M
innodb_data_file_path = ibdata1:10M:autoextend:max:128M
innodb_log_file_size = 5M
innodb_log_buffer_size = 8M
set-variable = innodb_log_files_in_group=2
innodb_flush_log_at_trx_commit = 1
innodb_lock_wait_timeout = 50
[mysqldump]
quick
max_allowed_packet                      = 16M
[mysql]
[isamchk]
key_buffer                                      = 20M
sort_buffer_size                        = 20M
read_buffer                             = 2M
write_buffer                            = 2M
[myisamchk]
key_buffer                                      = 20M
sort_buffer_size                        = 20M
read_buffer                             = 2M
write_buffer                            = 2M
[mysqlhotcopy]

[root@nexus ]# tail -n 18 /var/lib/mysql/nexus.err
071001 19:58:31  mysqld started
nohup: ignoring input
/usr/sbin/mysqld: Can't create/write to file '/tmp/iboidIUf' (Errcode: 13)
071001 19:58:31  InnoDB: Error: unable to create temporary file; errno: 13
071001 19:58:31 [ERROR] bdb:  /var/lib/mysql: Permission denied
071001 19:58:31 [ERROR] bdb:  /var/lib/mysql/log.0000000001: Permission denied
071001 19:58:31 [ERROR] bdb:  PANIC: Permission denied
071001 19:58:31 [ERROR] bdb:  PANIC: DB_RUNRECOVERY: Fatal error, run database recovery
071001 19:58:31 [ERROR] bdb:  fatal region error detected; run recovery
071001 19:58:31 [ERROR] bdb:  /var/lib/mysql: Permission denied
071001 19:58:31 [ERROR] Can't start server : Bind on unix socket: Permission denied
071001 19:58:31 [ERROR] Do you already have another mysqld server running on socket: /var/run/mysqld/mysqld.sock ?
071001 19:58:31 [ERROR] Aborting

071001 19:58:31 [Note] /usr/sbin/mysqld: Shutdown complete

071001 19:58:31  mysqld ended

any suggestions/help is appreciated.

Last edited by xhemi (2007-10-13 13:57:46)

Linteg

Member

From: Sweden

Registered: 2006-03-11

Posts: 54

Re: [SOLVED] /dev/md0 as the rootfs blockdevice

On a somewhat unrelated topic: Is there a reason why you would mount it with sync instead of the normal, and recommended, async?

xhemi

Member

From: /dev/urandom

Registered: 2007-03-14

Posts: 11

Website

Re: [SOLVED] /dev/md0 as the rootfs blockdevice

not anymore, i just wanted to verify that the system behaved the same way with async and sync.

i suspect this is a reiserfs issue, is anyone using reiserfs on a raid1?

i switched to jfs but the errors persists.

Last edited by xhemi (2007-10-03 21:40:55)

xhemi

Member

From: /dev/urandom

Registered: 2007-03-14

Posts: 11

Website

Re: [SOLVED] /dev/md0 as the rootfs blockdevice

i'm such an utter moron!

it was a permission issue on / itself, everything else had good perms... i just did a

chmod 755 /

and everything resolved itself!