2015年3月29日 星期日

How to login ubuntu with "root" account

How to login ubuntu with "root" account

1.Login with "user" account
2.# sudo passwd root
3. enter password
4. repeat password
5. Ctrl+Alt+F3
6. Login with "root"

2015年3月18日 星期三

The iSCSI boot does not work on RHEL7 with a static IP configured.

The iSCSI boot does not work on RHEL7 with a static IP configured.
from http://support.lenovo.com/gb/en/documents/ht100887


  1. Configure the iSCSI adapter and enable the boot from SAN feature.
  2. Enter the BIOS and change the boot mode to Legacy.
  3. Boot into the RHEL7.0 installation DVD and configure the NIC with a static IP address.
  4. Add a remote iSCSI target as a disk.
  5. Reboot after the installation completes and boot up will fail with the following error message:
[   2.375332] i8042: No controller found
[   2.592960] dracut: FATAL: For argument 'ip=::::localhost.localdomain:ens7:none'\nValue 'none' without static configuration does not make sense
[   2.593074] dracut: Refusing to continue
[   3.197719] System halted.

Workaround
iSCSI boot will succeed when adding the client IP address to the /boot/grub2/grub.cfg file.
Grub configuration files can be modified at the end of installation before rebooting.
To go to the shell and switch to the tty2 terminal (Ctrl-Alt-F2) or from the tmux screen on tty1, press Ctrl-B.  Then, change the configuration files of the installed system root mounted to /mnt/sysimage (eg /mnt/sysimage/boot/grub2/grub.cfg).
Example:
Before:
linux16 /vmlinuz-3.10.0-123.el7.x86_64 root=UUID=956c4dbb1-b287-42ba-94ec-f3c6b60c3361 ro vconsole.keymap=jp106 ip=::::localhost.localdomain:ens7:none... initrd16 /initramfs-3.10.0-123.el7.x86_64.img
After:
linux16 /vmlinuz-3.10.0-123.el7.x86_64 root=UUID=956c4dbb1-b287-42ba-94ec-f3c6b60c3361 ro vconsole.keymap=jp106 ip=192.168.122.10:::255.255.255.0:localhos... initrd16 /initramfs-3.10.0-123.el7.x86_64.img
Additional Information
This is a known issue of RHEL7.0.  This issue will be resolved in RHEL 7.1.

iSCSI CHAP

http://blog.csdn.net/sinchb/article/details/8433994#t10

1.What is CHAP?

Challenge-Handshake Authentication Protocol
iSCSI initiators and targets prove their identity to each other using the CHAP protocol, which includes a mechanism to prevent cleartext passwords from appearing on the wire.

2. iSCSI support two tpye chap authentication:

Initiator authentication和Target authentication

2.1 Initiator authentication

    When initiator(SUT) connect to target, initator should provide user name and password to target. The user name which initiator provdie is "incoming" account.
 Initiator authentication can  authentication independently, it call " Uni-directional Authentication",One way authentication

2.2 target authentication

    When initiator connect to target, target should provide user name and password to initiator. Tis is "outcoming" account

    target authentication have to authentication on both  initiator and target , it call " Bi-directional Authentication",Mutual  authentication
    iSCSI CHAP password length requirement must have 12~16 words

2015年3月13日 星期五

error 'Call "HostStorageSystem.ComputeDiskPartitionInfo" for object "storageSystem" on ESXi

 error 'Call "HostStorageSystem.ComputeDiskPartitionInfo" for object "storageSystem" on ESXi

The disk I was using had existing partitions (a Linux swap partition and a Linux MD5 RAID partition). 
Please manually delete the partitions logged in as root to ESXi shell.

Useful commands:
# esxcfg-scsidevs -l
this lists the disk devices, the device file will be /dev/disks/<NAME>
output looks like:
t10.ATA_____ST3320620AS_________________________________________6QF1PZXB
   Device Type: Direct-Access
   Size: 305245 MB
   Display Name: Local ATA Disk (t10.ATA_ST3320620AS_6QF1PZXB)
   Multipath Plugin: NMP
   Console Device: /vmfs/devices/disks/t10.ATA_____ST3320620AS_________________________________________6QF1PZXB
   Devfs Path: /vmfs/devices/disks/t10.ATA_____ST3320620AS_________________________________________6QF1PZXB
   Vendor: ATA       Model: ST3320620AS       Revis: 3.AA
   SCSI Level: 5  Is Pseudo: false Status: on
   Is RDM Capable: false Is Removable: false
   Is Local: true  Is SSD: false
   Other Names:
      vml.010000000020202020202020202020202036514631505a5842535433333230
   VAAI Status: unknown


# partedUtil get /dev/disks/t10.ATA_...
this shows the partitions on the device
output looks like:
38913 255 63 625142448
1 63 514079 130 128
2 514080 625137344 253 0

this disk has 2 partitions, numbers 1 and 2

# partedUtil delete /dev/disks/t10.ATA_... 2
deletes partition 2

# partedUtil delete /dev/disks/t10.ATA_... 1
deletes partition 1

If partedUtil doesn't work , pleate try "fdisk /dev/disks/t10.ATA......."  to delete partition.

2015年3月12日 星期四

How to execute Intel DCM (DataCenterManager)

How to execute Intel DCM (DataCenterManager)
Install this package on client with windows OS

1.Install Intel DCM
2.Install adobe flash
3.Open web browser
put in http://"computer-name":8688/DataCenterManager
4.Configuration=>Add group
5.Group=>Network discovery
Put in search ip address, BMC user name and password
6.Waiting for a few minutes, you can see the data change.

2015年3月11日 星期三

How to flash Primary/Backup BIOS from recovery mode (Intel platform)

How to flash Primary/Backup BIOS from recovery mode (Intel platform)

1.Adjust jumper to recovery mode
2.Boot to EFI shell

(大小寫有分別)
3.iflash32.efi -u xxxx.cap UpdateBackupBios

4.Adjust jumper to normal mode.

Simple dd command to test HDD read/write performance under linux

Simple dd command to test HDD read/write performance under linux Read #dd oflag=direct if=/dev/zero of=/mnt/test bs=512k count=200...