Shulou(Shulou.com)05/31 Report--

Today, I would like to talk to you about what suse linux 10 raw naked devices are like. Many people may not know much about it. In order to make you understand better, the editor has summarized the following for you. I hope you can get something according to this article.

Concept analysis:

Bare device: also known as bare partition (raw partition), is a special character device that is not formatted and is not read by Unix/Linux through the file system. Bare devices can be bound to either a partition or a disk.

System environment: SUSE LINUX ENTERPRISE SERVER 64BIT

The process of the experiment:

1. Create a bare device

Linux-250:~ # fdisk / dev/sda13 (view partition information)

He number of cylinders for this disk is set to 26108.

There is nothing wrong with that, but this is larger than 1024

And could in certain setups cause problems with:

1) software that runs at boot time (e.g.old versions of LILO)

2) booting and partitioning software from other OSs

(e.g., DOS FDISK, OS/2 FDISK)

Command (m for help): P

Disk / dev/sda13: 214.7 GB, 214753803264 bytes

255 heads, 63 sectors/track, 26108 cylinders

Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System

/ dev/sda13p1 1 13 104391 83 Linux

/ dev/sda13p2 14 26 104422 + 83 Linux

/ dev/sda13p3 27 39 104422 + 83 Linux

/ dev/sda13p4 40 26108 209399242 + 5 Extended

/ dev/sda13p5 40 76 297171 83 Linux

/ dev/sda13p6 77 138 497983 + 83 Linux

/ dev/sda13p7 139 145 56196 83 Linux

/ dev/sda13p8 146 152 56196 83 Linux

/ dev/sda13p9 153 159 56196 83 Linux

/ dev/sda13p10 160 161 16033 + 83 Linux

/ dev/sda13p11 16216316033 + 83 Linux

/ dev/sda13p12 164165 16033 + 83 Linux

/ dev/sda13p13 166167 16033 + 83 Linux

/ dev/sda13p14 168229 497983 + 83 Linux

/ dev/sda13p15 230291 497983 + 83 Linux

2. Bind bare devices

Found that there is no raw under / dev/, create your own raw directory

# mkdir raw

# cd raw

# mknod raw1 c 162 1

# mknod raw2 c 162 2

# mknod raw3 c 162 3

# mknod raw5 c 162 5

# mknod raw6 c 162 6

# mknod raw7 c 162 7

# mknod raw8 c 162 8

# mknod raw9 c 162 9

# raw/ dev/raw/raw1 / dev/sda13p1

-error

Cannot open master raw device

The raw command reports an error when configuring a bare device

Phenomenon description: in SLES10 SP3 system, using commands

# raw/ dev/raw/raw1 / dev/sda13p1 failed to attach bare device.

3. Cause analysis:

1. The possible reasons are:

1. Kernel compilation error.

2. Related module is not installed.

3. The relevant module is not loaded.

2. Module query method:

# zgrep-I raw / proc/config.gz

If the return is similar:

CONFIG_IEEE1394_RAWIO=m

CONFIG_IP_NF_RAW=y

CONFIG_IP6_NF_RAW=y

CONFIG_RAW_DRIVER is not set

It is reason 1 or reason 2 that causes the bare device to fail to hook up.

It is recommended to redeploy the operating system.

If the return is similar:

CONFIG_IP_NF_RAW=m

CONFIG_IP6_NF_RAW=m

CONFIG_IEEE1394_RAWIO=m

CONFIG_ARCNET_RAW=m

CONFIG_HDLC_RAW=y

CONFIG_HDLC_RAW_ETH=y

CONFIG_SERIO_RAW=m

CONFIG_RAW_DRIVER=m

CONFIG_MAX_RAW_DEVS=4096

CONFIG_SND_RAWMIDI=m

CONFIG_USB_SERIAL_SIERRAWIRELESS=m

It is reason 3 that causes the bare device to fail to connect.

4. Processing process:

1. Use the command # raw-qa to query the bare device and return an error:

Cannot open master raw device'/ dev/rawctl' (No such file or directory)

Second, use the command # zgrep-I raw / proc/config.gz query module

The following results are returned:

CONFIG_IP_NF_RAW=m

CONFIG_IP6_NF_RAW=m

CONFIG_IEEE1394_RAWIO=m

CONFIG_ARCNET_RAW=m

CONFIG_HDLC_RAW=y

CONFIG_HDLC_RAW_ETH=y

CONFIG_SERIO_RAW=m

CONFIG_RAW_DRIVER=m

CONFIG_MAX_RAW_DEVS=4096

CONFIG_SND_RAWMIDI=m

CONFIG_USB_SERIAL_SIERRAWIRELESS=m

Determine that reason 3 caused the bare device to fail to mount.

3. Load module to connect:

# modprobe raw

4. The same error will be reported after restart, so it needs to be solved thoroughly.

5. Run Yast configuration tool.

# yast2

Select System and select System Services (Runlevel).

Select Expert mode, select raw, and check Bmine2, Magi 3, 5.

Click Finish to save when configuration is complete.

6. Summary: it is recommended that if an error is reported during the deployment of the operating system, it should be redeployed.

And after deploying the system, check whether the necessary module is loaded.

Add:

1. Start raw mode

/ etc/init.d/raw start

two。 Set raw boot to activate automatically

Chkconfig-level 235 raw on

3. Check whether the raw boot is automatically activated.

Chkconfig-- list | grep raw

Review the chkconfig command:

The chkconfig command is mainly used to update (start or stop) and query the run-level information of system services. Keep in mind that chkconfig does not automatically disable or activate a service immediately, it simply changes symbolic connections.

Chkconfig-- list # lists the startup of all the services in the system

Chkconfig-add httpd # add httpd services

Chkconfig-- del httpd # Delete httpd service

Chkconfig-- level httpd 2345 on # sets httpd to be on when runlevels are 2, 3, 4 and 5

Chkconfig-- list mysqld # lists mysqld service settings

Chkconfig-- level 35 mysqld on # sets mysqld to boot at levels 3 and 5.-- level 35 indicates that the operation is only performed at levels 3 and 5, on indicates start, and off indicates shutdown.

Chkconfig mysqld on # sets mysqld to on at each level, and "each level" includes levels 2, 3, 4 and 5

-- level specifies at which execution level the read system service will be turned on or off.

Level 0 indicates that the computer is turned off

Level 1 means: single user mode

Level 2 means: multi-user command line mode without network connection

Level 3 means: multi-user command line mode with network connection

Level 4 means: not available

Level 5 means: multi-user mode with graphical interface

Level 6 means: restart

It is important to note that the level option specifies the runlevel to view, not necessarily the current runlevel. There can be only one start script or stop script per runlevel. When switching runlevels, init does not restart services that have already been started, nor does it stop services that have been stopped again.

After reading the above, do you have any further understanding of the suse linux 10 raw naked device? If you want to know more knowledge or related content, please follow the industry information channel, thank you for your support.

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