My IT Blog

ESXi 5.0 To avoid the rather complex set of instructions that you needed to follow in 4.1, VMware introduced new  detach  and  unmount operations to the vSphere UI & the CLI. As per  KB 2004605 , to avoid an APD condition in 5.0, all you need to do now is to  detach  the device from the ESX. This will automatically unmount the VMFS volume first. If there are objects still using the datastore, you will be informed. You no longer have to mess about creating and deleting rules in the PSA to do this safely. The steps now are: Unregister all objects from the datastore including VMs and Templates Ensure that no 3rd party tools are accessing the datastore Ensure that no vSphere features, such as Storage I/O Control or Storage DRS, are using the device Detach the device from the ESX host; this will also initiate an unmount operation Physically unpresent the LUN from the ESX host using the appropriate array tools Rescan the SAN

# setterm -powersave off -blank 0 Useful on the console of virtual hosts in vmware or virtualbox, for example.

What is an Inventory? An Inventory is the process of mounting media in the drive and reading the media label, which is then displayed in the  Devices  view. If this is the first time that Backup Exec ™ has encountered this media, the media label is also added to the  Media  view. Note : Each time new tape is introduced in the tape drive or robotic library, it must be inventoried so that the Backup Exec database gets updated with the new tape Information. To Inventory a Tape/Robotic Library: 1. Insert the tape 2. Click the  Devices  tab 3. Select the correct tape drive/robotic library slot 4. Right-click on the tape drive/robotic library slot and select  Inventory  (Figure 1) Figure 1 The inventory will complete and should display the correct tape name. What is a Catalog? When cataloging a tape, Backup Exec reads the header information from the tape and stores it in a file on the hard drive. The information contained in t...

Instead of configuring a virtual machine as a DHCP server, you can use the virtual DHCP server for your virtual network. To configure the virtual DHCP server: 1. Open the  Virtual Server Administration Website . 2. Under  Virtual Networks , select Configure  and then click the virtual network. 3. In  Virtual Network Properties , click  DHCP server . 4. Check the  Enabled  checkbox, then configure the necessary DHCP server options. 5. Click OK.

When the Remote Desktop Client is exited by pressing the ‘X’ on the control panel the remote session continues to run on the server even though no client is connected. Next time the user connects the desktop session will appear exactly as it was left before. To end the session select Start in the remote desktop session, click on the right arrow button in the bottom right hand corner of the menu and select Log Off. This will close down the remote desktop session and close the remote desktop client.

I always wonder how many throughput does a Virtual Machine consume when running in Hyper-V Host. Not always we dedicate a NIC for a Virtual Machine. For better consolidation, we always share several Virtual machine within a 1 Gbps NIC. Let say, you have 4 Virtual Machines running and share on 1 Gbps NIC. Will each Virtual Machine consume and limited to 250 Mbps? Well not really. Some VM will consume more throughput than 250 Mbps and will eventually impact the performance for the rest of the VM. This is what i found out when testing Hyper-V Vnext which seem like solving this case. On Virtual Network, you can configure to set minimum and maximum throughput per Mbps on each virtual machine. Great right…I’m excited to wait this feature available on next release of Hyper-V.

The Simple Network Time Protocol (SNTP) is a simpler version of the Network Time Protocol (NTP). SNTP synchronizes the time between networked computer systems and is relied on when data is being transferred via the Internet. The NTP protocol is one of the most established protocols still used on the Internet. It uses a GPS or radio clock to tell time and is accurate past the seconds place. Why is the SNTP Necessary? The need for precise time synchronization has continued to increase with the evolution of computer technology over the past several decades. In the networking field, network servers and their client computers require precision to the millisecond and beyond in order to ensure data file transfers occur without errors. Computers also require specific time synchronization in order to ensure data packet and email delivery in the proper sequence to destination networks and email recipients. The importance of the SNTP and NTP protocols exponentially expands with the number of...