Bright Cluster – HA Setup

  1. Configure failover interface in 1st Head Node
  2. Register license for HA
  3. Prepare HA configuration using command
     $ cmha-setup
  4. Go to Setup menu to prepare configuration
  5. Check Clone Failover for clone instruction
  6. Power-on second head node, let it boot to PXE
  7. Select Rescue in PXE menu
  8. Login as root
  9. Start cloning by calling
     $ /cm/cm-clone-install --failover
  10. The second head node will reboot automatically once completed
  11. Back to primary head node.
  12. In cmha-setup menu, select Finalize.
  13. Verify HA status
     $ cmha status
  14. In cmha-setup menu, configure shared storage.


EGO issue in IBM SCF CE


[root@pcmce-co68 ~]# egosh resource list
Cannot get host info. Not logged on.

Log in to egosh shell (one time only). Default user and password is Admin.

[root@pcmce-co68 ~]# egosh user logon
user account: Admin
Logged on successfully
[root@pcmce-co68 ~]# egosh resource list
NAME status mem swp tmp ut it pg r1m r15s r15m ls
pcmce-c* ok 827M 1516M 69G 7% 258 3.1 0.2 3.3 0.7 1


Disable Serial Console Redirection in xCAT

PXE boot config:

"... console=tty0 console=ttyS0,115200 ..."

Note: serial console redirection is managed by hardware profile.

To check hardware profile:

$ tabdump nodehm

To disable: clear the entries of serialport, serialspeed and serialflow columns

$ chdef -t group -o __HardwareProfile_IBM_Flex_System_x serialport= serialspeed= serialflow=


How to Configure Mellanox Switch

Required Tools:

  1. Serial console cable (provided inside the box)
  2. Converter cable from serial port to USB port (Prolific)

Step-by-step guide using MacOS:

  1. Download and install driver for the converter cable
  2. Check if the driver is installed correctly
     $ kextstat | grep prolific
     159 0 0xffffff7f832fa000 0x6000 0x6000 com.prolific.driver.PL2303 (1.6.0) F6A6805D-685D-3E6D-BF81-106EBBC0A386
     $ ioreg -c IOSerialBSDClient | grep usb
     | | "IOTTYBaseName" = "usbserial"
     | | "IOCalloutDevice" = "/dev/cu.usbserial"
     | | "IODialinDevice" = "/dev/tty.usbserial"
     | | "IOTTYDevice" = "usbserial"
  3. Start the connection
     $ screen /dev/cu.usbserial
  4. Press Enter and follow instructions in official user guide.
    For example:
Mellanox Switch

Mellanox configuration wizard
 Do you want to use the wizard for initial configuration? y
 Step 1: Hostname? [switch-56d680] switch-10g
 Step 2: Use DHCP on mgmt0 interface? [yes] no
 Step 3: Use zeroconf on mgmt0 interface? [no] no
 Step 4: Primary IPv4 address and masklen? []
 Step 5: Default gateway?
 Step 6: Primary DNS server?,
 % Value must be an IPv4 address in the format of ''.
 Step 6: Primary DNS server?
 Step 7: Domain name?
 Step 8: Enable IPv6? [yes] yes
 Step 9: Enable IPv6 autoconfig (SLAAC) on mgmt0 interface? [no] no
 Step 10: Enable DHCPv6 on mgmt0 interface? [no] no
 Step 11: Admin password (Enter to leave unchanged)?
 Step 11: Confirm admin password?
 You have entered the following information:
 1. Hostname: switch-10g
 2. Use DHCP on mgmt0 interface: no
 3. Use zeroconf on mgmt0 interface: no
 4. Primary IPv4 address and masklen:
 5. Default gateway:
 6. Primary DNS server:
 7. Domain name:
 8. Enable IPv6: yes
 9. Enable IPv6 autoconfig (SLAAC) on mgmt0 interface: no
 10. Enable DHCPv6 on mgmt0 interface: no
 11. Admin password (Enter to leave unchanged): (CHANGED)
 To change an answer, enter the step number to return to.
 Otherwise hit to save changes and exit.

digsby = im + email + social networks + Cloud Computing

ni aplikasi, idenya keren juga neh,.. nggabungin instant messenger, email dan social networks dalam satu aplikasi.. jadi bisa ym-an, ngcek email, ama fesbukan dalam satu aplikasi.. keren kan yakk ?? ga yah ?? keren ajalah bilang, ya ya ??.. hehe


tapi yang menarik buat gw bukan itu.. 😀 ternyata ni aplikasi support cloud computing.. apa itu cloud computing ?? gw jg ga terlalu paham detailnya seperti apa sebenarnya.. 😀  tp pas gw di Taiwan, teknologi ini sempat gencar dikenalkan ke kampus-kampus disana oleh Google Taiwan.. intinya sih, computing berbasis internet.. jadi melalui sebuah aplikasi internet seseorang bisa memanfaatkan kompie dibelahan dunia lain buat mengerjakan komputasinya..

nah, katanya si Digsby ini punya fitur buat cloud computing tersebut.. fitur tersebut bisa di-aktif/mati kan sesuai kemauan si pemilik kompie kok.. kalau kita aktif kan, maka ketika kompie dalam kondisi idle, si digsby akan memanfaatkan kompie kita untuk mengerjakan komputasi tertentu.. 🙂

NFS Server dan Client

Salah satu bagian penting dalam ngebangun linux cluster adalah NFS. NFS singkatan dari Network File System. Dengan menggunakan NFS, user di kompie client dapat dengan mudah mengakses file di server semudah mengakses di lokal direktori.

Pada artikel ini versi yang digunakan adalah fedora 8. Ada 4 paket yang harus di install di server dan client, yaitu:

  1. glibc-utils, yang merupakan development utilities dari GNU C library.
  2. nfs-utils-lib-devel, yakni development files untuk nfs-utils-lib library
  3. nfs-utils-lib, yakni NFS support library
  4. nfs-utils, yakni NFS utilities

Berikut settingan pada NFS server. Read More …

multithreading in linux

Below is a sample multithreading program based on C language.

[sourcecode language=’cpp’]

# include

/* parameter that will be passed to each matrix */
struct v{


/* function that will be executed in each thread */
void *runonThread(void *param){
struct v* data = (struct v*) param;
/* put your application here */

int main()
pthread_t pid[NUMTHREADS];
pthread_attr_t attr;

/* get the default attributes */

for(i=0; i… = … ;
/*passing ‘data’ as parameter to each thread*/
pthread_create(&pid[i], &attr,
runonThread, data);

/*waiting for the threads to complete */
for(i=0; i<NUMTHREADS; i++)
pthread_join(pid[i], NULL);

return 0;

You may download a sample application to count matrix multiplication that uses multithreads,