Dark Developments Where Knowledge Meets Power

11Oct/110

VMware – ESX(i) Jumbo Frames on Storage Adapters

Posted by Dark#Basics

VMware - ESX(i) Jumbo Frames on Storage Adapters
Jumbo frames are units that contain 9,000 bytes of data instead of the usual 1500, or an MTU of 9000 instead of 1500.  When using the ESX software iSCSI initiator, a network adapter becomes the transport device for your iSCSI traffic.  When creating a virtual switch using the vSphere client, you cannot change the default MTU value of 1500, nor can you even view the values

If the software Storage Adapters are already created the MTU can still be modified using the CLI of your host.
First check the current vSwitches so that you can confirm the changes and settings.

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esxcfg-vswitch -l

Run vmknic to change the MTU of all the vSwitches.

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esxcfg-vmknic -m 9000 "VMkernel iSCSI 2"
3Oct/110

ASTERISK – Installing Asterisk on Debian

Posted by Dark#Basics

ASTERISK - Installing Asterisk on Debian
These instructions installs the components necessary for a standard asterisk configuration. I assume a fresh installation of Debian is installed.

Begin making sure that the package lists is recent:

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root@DEBIANX32: apt-get update

And upgrade the current packages to the most recent version:

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root@DEBIANX32: apt-get upgrade

First, we must install a working build environment that includes a compiler, linker, etc so that we can configure, compile and install Asterisk.

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root@DEBIANX32: apt-get install build-essential
root@DEBIANX32: apt-get install libncurses5-dev bison libssl-dev libnewt-dev zlib1g-dev procps gcc make binutils doxygen

Next install the necessary Linux kernel headers, first we need to find the current version.

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root@DEBIANX32: uname -r
2.6.32-5-686

Then when we know the version we'll install the correct package.

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root@DEBIANX32: apt-get install linux-headers-2.6.32-5-686

Now that the operating system is ready we'll download Asterisk and start the installation. First we'll download the package by issuing wget.

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root@DEBIANX32: wget %downloadlinkhere%

When the package is installed we'll unpack the TAR-ball.

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root@DEBIANX32: tar -xvf %packagename%

To prepare the installation, run the configure scropt with the Asterisk sources.

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root@DEBIANX32: cd asterisk-%version%
root@DEBIANX32: ./configure

Now we'll begin the compiling.

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root@DEBIANX32: make

Finally install the compiled sources by invoking make install.

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root@DEBIANX32: make install

After this all the necessary libraries and other resources are installed but you'll notice that the configuration directory is completly empty. Get the sample configuration files by issuing the make samples command.

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root@DEBIANX32: make samples

Note: Use only for a fresh install, might overwrite your config!

To setup Asterisk to start and stop automaticly with the system we'll need to init the scripts.

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root@DEBIANX32: make config
Filed under: Asterisk, Linux No Comments
3Oct/110

EXCHANGE – Recovering a Disconnected MailBox

Posted by Dark#Basics

EXCHANGE - Recovering a Disconnected MailBox
After disabling a mailbox it will still be present in the mailbox store and it is marked for removal. During maintenance, the MSExchangeIS process will check for mailboxes marked for removal and which are past their retention period. The retention period is a configurable setting and by default it is set to 30 days, meaning you can recover deleted mailboxes within 30 days.

Perhaps unnecessary to say, but don’t select Remove to remove a mailbox. The Remove option will not only disconnect the mailbox but will also delete the associated user object. You will not be the first to accidentally remove the user object when you only intended to remove the mailbox selecting the Remove option. After all, you are in a Mailbox view so Remove implies removing a mailbox. The action Disable is also improper naming since it doesn’t disable the mailbox but marks the mailbox for deletion. After the retention period it will be deleted permanently. That’s not what “Disable” implies. After all, disabled user accounts are not deleted from the Active Directory after their tombstone expires.

To disable a mailbox from the Exchange Management Shell use the Disable-Mailbox:

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Disable-Mailbox <UserID>

Note that disconnected mailboxes may not show up immediately because of delays caused by replication or if the status of the mailbox hasn’t been updated in the store yet.

When a mailbox is disconnected you will be able to connect the mailbox again using the Exchange Management Console or by using the Exchange Management Shell.

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Connect-Mailbox –Identity <MailboxID> -Database <DatabaseID> -User < UserID>