Linux 基础知识（六.二）

1、复制/etc/rc.d/rc.sysinit至/tmp目录，将/tmp/rc.sysinit文件中的以至少一个空白字符开头的行的行首加#

[root@server01 tmp]# cp /etc/rc.d/rc.sysinit /tmp/

[root@server01 tmp]# sed -n "s@^[[:space:]]\+@#&@gp" rc.sysinit

# . /etc/sysconfig/network
# HOSTNAME=localhost
# mount -n -t proc /proc /proc
# mount -n -t sysfs /sys /sys >/dev/null 2>&1
# modprobe usbcore >/dev/null 2>&1 && mount -n -t usbfs /proc/bus/usb /proc/bus/usb
# mount -n -t usbfs /proc/bus/usb /proc/bus/usb
# if [ -r "/selinux/enforce" ] ; then
# SELINUX_STATE=$(cat "/selinux/enforce")
# else
# # assume enforcing if you can't read it
# SELINUX_STATE=1
# fi
……
# chmod 0664 /var/run/utmpx /var/log/wtmpx
# /tmp/kde-* /tmp/ksocket-* /tmp/mc-* /tmp/mcop-* /tmp/orbit-* \
# /tmp/scrollkeeper-* /tmp/ssh-* \
# /dev/.in_sysinit
# curswap=$(awk '/^\/dev/ { print $1 }' /proc/swaps | while read x; do get_numeric_dev dec $x ; echo -n " "; done)
# swappartitions=$(blkid -t TYPE=swap -o device)
# if [ x"$swappartitions" != x ]; then
# for partition in $swappartitions ; do
# [ ! -e $partition ] && continue
# majmin=$(get_numeric_dev dec $partition)
# echo $curswap | grep -qw "$majmin" || action $"Enabling local swap partitions: " swapon $partition
# done
# fi
# if strstr "$cmdline" netprofile= ; then
# for arg in $cmdline ; do
# if [ "${arg##netprofile=}" != "${arg}" ]; then
# /usr/sbin/system-config-network-cmd –profile ${arg##netprofile=}
# fi
# done
# fi
# touch /var/run/confirm
# /bin/plymouth –sysinit

2、复制/boot/grub/grub.conf至/tmp目录，删除/tmp/grub.conf文件中的行首的空白字符

[root@server01 tmp]# cp /boot/grub/grub.conf /tmp/

[root@server01 tmp]# sed -n "s@^[[:space:]]\+@@p" grub.conf

root (hd0,0)
kernel /vmlinuz-2.6.32-573.el6.x86_64 ro root=/dev/mapper/vg_server01-lv_root rd_NO_LUKS rd_LVM_LV=vg_server01/lv_root.UTF-8 rd_NO_MD SYSFONT=latarcyrheb-sun16 crashkernel=auto rd_NO_DM KEYBOARDTYPE=pc KEYTABLE=us rd_LVM_LV=vg_server01/lv_swap rhgb quiet
initrd /initramfs-2.6.32-573.el6.x86_64.img

3、删除/tmp/rc.sysinit文件中以#开头，且后面跟了至少一个空白字符的行的#和空白字符

[root@server01 tmp]# sed -rn "s@^#[[:space:]]+@@p" rc.sysinit

/etc/rc.d/rc.sysinit – run once at boot time
Taken in part from Miquel van Smoorenburg's bcheckrc.
Check SELinux status
Print a text banner.
Only read this once.
Initialize hardware
Set default affinity
Load other user-defined modules
Load modules (for backward compatibility with VARs)
Configure kernel parameters
Set the hostname.
Sync waiting for storage.
Device mapper & related initialization
Start any MD RAID arrays that haven't been started yet
Remount the root filesystem read-write.
Clean up SELinux labels
If relabeling, relabel mount points.
Mount all other filesystems (except for NFS and /proc, which is already
mounted). Contrary to standard usage,
filesystems are NOT unmounted in single user mode.
The 'no' applies to all listed filesystem types. See mount(8).
Update quotas if necessary
Check to see if a full relabel is needed
Initialize pseudo-random number generator
Configure machine if necessary.
Clean out /.
Do we need (w|u)tmpx files? We don't set them up, but the sysadmin might…
Clean up /var.
Clean up utmp/wtmp
Clean up various /tmp bits
Make ICE directory
Start up swapping.
Set up binfmt_misc
Boot time profiles. Yes, this should be somewhere else.
Now that we have all of our basic modules loaded and the kernel going,
let's dump the syslog ring somewhere so we can find it later
create the crash indicator flag to warn on crashes, offer fsck with timeout
Let rhgb know that we're leaving rc.sysinit

4、为/tmp/grub.conf文件中的前三行的行首加#号

[root@server01 tmp]# sed -n "1,3s@^@#@p" grub.conf

## grub.conf generated by anaconda
##
## Note that you do not have to rerun grub after making changes to this file

5、将/etc/yum.repos.d/CentOS-Media.repo文件中所有的enabled=0或gpgcheck=0修改最后的0为1

[root@server01 tmp]# sed -rn "s@(enabled|gpgcheck)=0@\1=1@p" /etc/yum.repos.d/CentOS-Media.repo

enabled=1

6、每4小时执行一次对/etc目录的备份，备份至/backuup目录中，保存的目录名称为形如etc-201504020202

[root@server01 tmp]# crontab -e

*** /4 * * /bin/tar cvf /backup/etc-$(date +%Y%m%d%H%M%S) /etc/***

7、每周2，4，6备份/var/log/messages文件至/backup/message_logs目录中，保存的文件名形如messages-20160402

[root@server01 tmp]# crontab -e

* * * * 2,4,6 /bin/cp /var/log/messages /backup/message_logs/messages-$(date +%Y%m%d)

8、每天每两小时取当前系统/proc/meminfo文件中的所有以S开头的信息至/stats/memory.txt文件中

[root@server01 message_logs]# mkdir /stats

[root@server01 ~]# crontab -e

* /2 * * /bin/cat /proc/meminfo | /bin/grep -E "^[S]" &> /stats/memory.txt

9、工作日的工作时间内，每两小时执行一次echo "howdy"

[root@server01 ~]# crontab -e

* 9-18/2 * * 1,2,3,4,5 /bin/echo "howdy"

原创文章，作者：Tornado，如若转载，请注明出处：http://www.178linux.com/55335

Linux 基础知识（六.二）

1、复制/etc/rc.d/rc.sysinit至/tmp目录，将/tmp/rc.sysinit文件中的以至少一个空白字符开头的行的行首加#

[root@server01 tmp]# cp /etc/rc.d/rc.sysinit /tmp/

[root@server01 tmp]# sed -n "s@^[[:space:]]\+@#&@gp" rc.sysinit

# . /etc/sysconfig/network

# HOSTNAME=localhost

# mount -n -t proc /proc /proc

# mount -n -t sysfs /sys /sys >/dev/null 2>&1

# modprobe usbcore >/dev/null 2>&1 && mount -n -t usbfs /proc/bus/usb /proc/bus/usb

# mount -n -t usbfs /proc/bus/usb /proc/bus/usb

# if [ -r "/selinux/enforce" ] ; then

# SELINUX_STATE=$(cat "/selinux/enforce")

# else

# # assume enforcing if you can't read it

# SELINUX_STATE=1

# fi

……

# chmod 0664 /var/run/utmpx /var/log/wtmpx

# /tmp/kde-* /tmp/ksocket-* /tmp/mc-* /tmp/mcop-* /tmp/orbit-* \

# /tmp/scrollkeeper-* /tmp/ssh-* \

# /dev/.in_sysinit

# curswap=$(awk '/^\/dev/ { print $1 }' /proc/swaps | while read x; do get_numeric_dev dec $x ; echo -n " "; done)

# swappartitions=$(blkid -t TYPE=swap -o device)

# if [ x"$swappartitions" != x ]; then

# for partition in $swappartitions ; do

# [ ! -e $partition ] && continue

# majmin=$(get_numeric_dev dec $partition)

# echo $curswap | grep -qw "$majmin" || action $"Enabling local swap partitions: " swapon $partition

# done

# fi

# if strstr "$cmdline" netprofile= ; then

# for arg in $cmdline ; do

# if [ "${arg##netprofile=}" != "${arg}" ]; then

# /usr/sbin/system-config-network-cmd –profile ${arg##netprofile=}

# fi

# done

# fi

# touch /var/run/confirm

# /bin/plymouth –sysinit

2、复制/boot/grub/grub.conf至/tmp目录，删除/tmp/grub.conf文件中的行首的空白字符

[root@server01 tmp]# cp /boot/grub/grub.conf /tmp/

[root@server01 tmp]# sed -n "s@^[[:space:]]\+@@p" grub.conf

root (hd0,0)

kernel /vmlinuz-2.6.32-573.el6.x86_64 ro root=/dev/mapper/vg_server01-lv_root rd_NO_LUKS rd_LVM_LV=vg_server01/lv_root.UTF-8 rd_NO_MD SYSFONT=latarcyrheb-sun16 crashkernel=auto rd_NO_DM KEYBOARDTYPE=pc KEYTABLE=us rd_LVM_LV=vg_server01/lv_swap rhgb quiet

initrd /initramfs-2.6.32-573.el6.x86_64.img

3、删除/tmp/rc.sysinit文件中以#开头，且后面跟了至少一个空白字符的行的#和空白字符

[root@server01 tmp]# sed -rn "s@^#[[:space:]]+@@p" rc.sysinit

/etc/rc.d/rc.sysinit – run once at boot time

Taken in part from Miquel van Smoorenburg's bcheckrc.

Check SELinux status

Print a text banner.

Only read this once.

Initialize hardware

Set default affinity

Load other user-defined modules

Load modules (for backward compatibility with VARs)

Configure kernel parameters

Set the hostname.

Sync waiting for storage.

Device mapper & related initialization

Start any MD RAID arrays that haven't been started yet

Remount the root filesystem read-write.

Clean up SELinux labels

If relabeling, relabel mount points.

Mount all other filesystems (except for NFS and /proc, which is already

mounted). Contrary to standard usage,

filesystems are NOT unmounted in single user mode.

The 'no' applies to all listed filesystem types. See mount(8).

Update quotas if necessary

Check to see if a full relabel is needed

Initialize pseudo-random number generator

Configure machine if necessary.

Clean out /.

Do we need (w|u)tmpx files? We don't set them up, but the sysadmin might…

Clean up /var.

Clean up utmp/wtmp

Clean up various /tmp bits

Make ICE directory

Start up swapping.

Set up binfmt_misc

*** /4 * * /bin/tar cvf /backup/etc-$(date +%Y%m%d%H%M%S) /etc/***

* /2 * * /bin/cat /proc/meminfo | /bin/grep -E "^[S]" &> /stats/memory.txt