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Key applications on Mac such as iMessage, FaceTime and even Facebook integration with Notifications depend on your Mac's Serial Number. If the System Information is showing #Serial Number, you will not be able to sign in.

To solve, search for Blank Board Serializer.

redhat disable ipv6

* /etc/sysconfig/network - add "NETWORKING_IPV6=no"
* /etc/sysctl.conf - add "net.ipv6.conf.all.disable_ipv6 = 1"

# hdiutil convert -format UDRW -o ~/path/to/target.img ~/path/to/ubuntu.iso
# diskutil list
# diskutil unmountDisk /dev/diskN
# sudo dd if=/path/to/downloaded.img of=/dev/rdiskN bs=1m
# diskutil eject /dev/diskN

Re-build Grub on Proliant

/etc/grub.conf
boot=/dev/cciss/c0d0


/boot/grub/device.map
(fd0)     /dev/fd0
(hd0)    /dev/cciss/c0d0

/sbin/grub --batch --device-map=/boot/grub/device.map \
   --config-file=/boot/grub/grub.conf --no-floppy
grub> root (hd0,0)
grub> setup (hd0)
grub> quit

original

Issues after upgrading SuSE

1. Permission of /root is 710 by default after upgrade
2. Timezone may change
3. If server is configured with kdump enabled, Kdump parameter is not preserved in /boot/grub/menu.lst

no gdm and gnome in sles 11

ensure repo is good
zypper install -t pattern x11 gnome
edit /etc/sysconfig/displaymanager and windowmanager
default_wm=gnome
default_display=gdm
check /root perm
init 5

remove ^M characters in vim

:%s/^M//g where ^M is entered by ctrl+V and ctrl+M

set vxdisk to use persistent dsf (agile)

# vxddladm set namingscheme=osn mode=new

network throughput rate

sar -n DEV 1 3

ps process which is fuser a fs

ps -fp `fuser -m /tmp`

get total sum of filesystem usage

df -mP | awk '{sum += $3;} END {print sum;}'