Eskiden çok sevdiğim bir sitede vardı: Tamamen boş, fonksiyonu olmayan bir buton :) "stress tuşunda anlam arayan varsa, derhal siteyi terketsin..."

Olayı abartmamak lazım tabi:

View Ertürk İhsan Limon's profile on LinkedIn

Red Hat Certified Engineer

VCP5 Certified

VCP6-DCV Certified

one of the greatest actors of all times

I can watch this a thousand times.

Errors in NTP Auth configuration using autokey

During latest leap second test activities, I was tinkering with my test NTP server and I encountered an error: "RAND_load_file /root/.rnd not found or empty"

There is not much help on internet. You just need to seed with the following command:
dd if=/dev/urandom of=/root/.rnd bs=512 count=1

And if you have an error: "crypto_setup: random seed file not found error:"
Add “crypto randfile /dev/urandom” entry to /etc/ntp.conf without the quotes.

For details:

about being human

Bernard : Lifelike, but not alive. Pain always exists in the mind; it’s always imagined. So what’s the difference between my pain and yours, between you and me?

Ford : This was the very question that consumed Arnold, filled him with guilt, eventually drove him mad. The answer always seemed obvious to me. There is no threshold that makes us greater than the sum of our parts, no inflection point at which we become fully alive. We can’t define consciousness because consciousness does not exist. Humans fancy that there’s something special about the way we perceive the world, and yet we live in loops, as tight and as closed as the hosts do, seldom questioning our choices, content, for the most part, to be told what to do next. No, my friend, you’re not missing anything at all.


Ford : I’ve told you, Bernard, never place your trust in us. We’re only human. Inevitably, we’ll only disappoint you. Goodbye my friend.


Felix : Are you sure you’re gonna be okay?
Maeve : Oh, Felix. You really do make a terrible human being. And I mean that as a compliment.

HP Smart Array B140i SATA RAID controller OS boot problem

Recently I installed VMware ESXi on a HP DL160 Gen9 server and couldn’t boot afterwards. After a short investigation I found out that the default configuration of the controller prevents booting. The controller should be configured and enabled to support SATA AHCI mode. Actually it is necessary to configure it for all servers carrying HP Smart Array B110i, B120i, B140i and B320i RAID controllers.

To do that:

1) In BIOS/UEFI, go into “System Options”
2) Go to SATA Controller Options -> Embedded SATA Configuration
3) Select “Enable SATA AHCI Support”

For a similar case in RedHat:

WWN / MAC Formatter

Since I first dealt with SANs and WWNs years ago, I thought there should be a more practical way to edit WWNs, most of the time to add colons between characters. I could not find an online tool to do this. One can and possibly does use a little more advanced text editor to do block editing or some custom scripting to do this task. I wanted to make it easier and also share with others so I decided to build a php tool here. With adding some features and extending the idea to MACs, this came out:

WWN/MAC Formatter

I hope it helps other system administrators.

Exporting images from headers or footers in Excel 2007 and 2010

If you don’t have the original file of an image used in a Excel file header or footer and you need it, here is a solution: All Office 2007, 2010… files are actually zipped files. If you have an older version, Excel 97-2003 (.xls), just save it as Excel 2007-2010 workbook (with extension .xlsx). Just renaming does not work. If you open .xlsx file with a program that can open .zip (7Zip, WinRAR or WinZip) you will see some folders. The files you are looking for are in folder “xl\media” and you can easily extract them from there. You may copy the file and work on the copy if you want to be on the safe side.

ölmeyen adam

“Bu hayatta herkesin bir derdi var Cemal. Benimki de bu. Ölemiyom be ..ına koyayım. Eyi bi şey sanıyon bunu demi? Herkesler öyle sanıyor ama gel bir de bana sor. En berbat tarafı ne biliyon mu? Hiç kimseden hiçbir şeyden korkun kalmıyor. Ar damarı çatlıyor adamın. Doğru ne yanlış ne her şey karışıyor kafanda. Bu ..ına koduklarımın 100 sene önce neye inandıklarını görsen çok gülersin. Ben biliyom mesela. 100 sene sonra neye inanacaklar onu da biliyo olcem. Ya her şeyleri biliyom ben Cemal. Hee her şeyleri bilmekle hiçbir şey bilmemek aynı şey. Odun gibi oluyon işte. Onun için çok fazla kurcalamicen meseleleri. Eninde sonunda ölcek olan birisinin bu dünyanın derdini çözmesine imkan yok.”

Bad Liar, Good Liar

Lisbon : Did you know about it?
Woman : Of course. He told me everything.
Jane : I-ıh, liar. Bad liar.
Woman : How dare you?
Jane : Well, it’s a compliment to a good character. You rather be a good liar?

Installing VMware ESXi on IBM Lenovo x240 M5 with SD Media Adapter and SD Cards

Last week I installed VMware ESXi 6.0U1B on some (formerly IBM) Lenovo x240 M5 Compute Nodes in Flex System Chassis. The case was special because the nodes contain only SD cards and SD Media Adapters instead of SAS hard drives and standard RAID controllers. There are no interface other than IMM CLI of the node to configure this SD Media Adapter to build a RAID array. You should first connect to IMM of the node with SSH. Then you can get the initial information about your SD RAID and cards with these commands:

system> sdraid
SD Media Adapter for System x
Hardware Revision = 4.3
Firmware Version =
Serial Number = 58WXYZ
FRU Number = 00JY0XX
Mode = Operational
Status = Healthy
Capacity = 30436 MBytes
FRU Number = 00MLXYZ
Status = Healthy
Capacity = 30436 MBytes
FRU Number = 00MLXYZ

system> sdraid -driveList
SDCard 1
Index LUN Name Type Size(MB) Owner Access Removable
SDCard 2
Index LUN Name Type Size(MB) Owner Access Removable

system> sdraid -getFreeSpaceInfo

I have two 32 GB SD cards which I intend to build a mirror RAID-1 array with. I switched to config mode, created the drive and switched back to operational mode with these commands:

system> sdraid -setMode Configuration -now
system> sdraid -create -driveName ESXiLocalDS -target mirror -sizeMB 30436 -removable 1 -owner system -systemReadOnly 0 -LUN 0
system> sdraid -setMode Operational -now

After these BIOS should be configured to boot from this drive:

Boot Manager > Add Boot Option > Generic Boot Option > Embedded Hypervisor
Boot Manager > Change Boot Order > move "Embedded Hypervisor" to the top
System Settings > Devices and I/O Ports > PCI 64-Bit Resource > Disabled
System Settings > Devices and I/O Ports > MM Config Base > 3 GB

When you save your changes and exit BIOS, you will be able to start ESXi installation aware of the SD card drive.

For reference:

Converting Thin Provisioned Disks to Lazy Zeroed Thick in VMware vSphere

Lately I’ve dealt with a problem about thin-provisioned disks in my vSphere environment. Although there is the feature in VMware, I choose to leave thin provisioning to back-end, to storage administrators. The usage may go beyond your control in short time and you may not be able to receive disk resource during that time. It is just about to be on the safe side: “I do not use thin provisioning in VMware virtual disks.”

Unfortunately before me one datastore was over-provisioned (over 200%!!) and left unattended. It was only a short time after taking over and clients decided to use the resource which was promised to them. We received a call about a VM that went unresponsive and as we dig we understood the severity of the situation.

In short, we received new LUNs and moved VMs to new datastores. I took an action to convert all the thin provisioned disks to thick. It is officially done with right clicking the thin provisioned vmdk file in the datastore browser and choosing “Inflate”:

inflate vmdk

However this triggers a conversion to eager zeroed thick provisioned disk. It takes more time and creates unnecessary I/O on storage side. To convert the provisioning of disks to lazy zeroed thick I initiated Storage vMotion with the appropriate virtual disk format selection:

Storage vMotion

After the successful migration the virtual disks of VM is lazy zeroed thick provisioned. GUI may still show “Used Space 0.00B” about VM. A refresh on the Datastore Summary / Capacity Usage page should correct the glitch.

To automate the process you can use the following command in PowerCLI:

Move-VM -VM thinvm -Datastore differentdatastore -DiskStorageFormat Thick