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Barracuda NG Firewall: exclude Apple Appstore from AV scanning
edited by on October 22nd 2018, at 10:35
Barracuda NG Firewall has a comprehensive anti-malware and anti-virus scanning engine. Unfortunately, this clashes with the Apple Appstore: downloading apps and updates get blocked by the AV scanning engine. In order to resolve this, the URLs from Apple need to be excluded.

Using NGAdmin, log on to the firewall (or Control Center), navigate to the Virus-Scanner service of the firewall, and open the Virus Scanner Settings configuration node.

Click on Content Scanning and under the HTTP Multimedia Streaming section, add a new Scan Exception.

Enter a name for the exclusion, then enter these values:

Allowed MIME-Types: add the value *

Domain: *.apple.*

Setting the allowed MIME-type to * is  ...
 
VMWare: mark all optical drives as client
edited by on September 27th 2018, at 11:38
It is best practice not to have an ISO mounted on a VM if it is not necessary. This is especially the case with VDI: if you forget to set the optical drive back to client, each of your desktops will have the ISO mounted as well, which can create a hassle with dependencies on the datastore where the ISO is located.

With PowerCLI, you can quickly resolve the matter with this one-liner:

Get-VM | Get-CDDrive | Where {$_.ISOPath -ne $null} | Set-CDDrive -NoMedia -Confirm:$false

For VDI, note that this will not work for replicas and master images containing snapshots, as the dependency remains intact if a snapshot exists where the ISO was still mounted. In that case, it is better to clone the m  ...
 
Add/remove network routes in macOS
edited by on September 27th 2018, at 10:35

Similar as on FreeBSD and Linux, you can add/remove static network routes through the command line with the route command. The syntax somewhat differs from Linux, though.

To add a route (e.g. subnet 192.168.3.0/24 to gateway 192.168.1.254):

sudo route -n add -net 192.168.3.0/24 192.168.1.254

To remove a route:

sudo route -n delete -net 192.168.3.0/24

To show the current route table, you can use netstat:

netstat -nr
 
macOS: reset folder view for all folders
edited by on September 27th 2018, at 10:15
Folder view preferences are stored separately in a hidden file called .DS_Store in each folder. If you want to reset the folder view options to the default settings, you can use Terminal to do a search for those files and remove them.

To remove them in your home folder, you can run this:

find ~ -name ".DS_Store" -delete

Note that you can also do this on network shares. Just adjust the search path accordingly.

Suppose you have a share mapped to smb://server/data, then you would type:

find /Volumes/data -name "*.DS_Store" -delete

Caution
Be very careful with this command. It will not ask for confirmation!Making a typo (like forgetting to add the -name parameter) could result in permanent  ...
 
Backup switch configuration to TFTP (CLI reference)
edited by on August 24th 2018, at 15:14
In case of disaster, it is usually a very good idea to periodically back up the configuration of your network switches. This article lists syntax for backing up configuration to a TFTP server for different vendors.

In the syntax examples below, the IP for the TFTP is 1.2.3.4, and we're writing to the file switch.cfg.

Note that this article is definitely not complete. If you have additions to this article, please post them in the comments.

The syntax for Dell and Cisco switches is mostly the same. For N-series and PowerConnect, a summary is displayed which needs to be confirmed, which is not the case for Cisco and Dell S-series.

For Cisco Small Business (SF- and SG-series), the CLI ne  ...
 
Enable Telnet/SSH on Cisco 300/500 switches
edited by on August 21st 2018, at 14:44

Cisco's SF/SG 300/500 series managed switches have CLI access via Telnet and SSH but this is turned off by default, leaving only the web interface to manage the switch. You can enable Telnet and/or SSH via the web interface, enabling management via CLI.

  1. Log on to the web interface, then navigate to Security → TCP/UDP Services.
  2. Check the Enable boxes for Telnet Service and/or SSH Service. You can check both if you wish to enable both protocols. Click Apply, which will immediately start the selected services:
  3. Don't forget to save the configuration change to flash. Otherwise, the change will be lost after a reboot:
 
Configure tftpd-hpa to allow upload of new files
edited by on August 21st 2018, at 14:16
When installing tftpd-hpa, as a security measure, the service does not allow uploading new files. It does allow overwriting existing files, provided that the permissions are set correctly (as expected). The idea behind this is to secure TFTP a bit by only allowing uploads if the file already exists (and is writable). But this can be very tedious in some cases, where a lot of files have to be uploaded, and it is not possible to guess the names to create them in advance.

It is possible to configure tftpd-hpa to allow the creation of new files by adding the -c or --create parameter when starting the daemon.

For Ubuntu and Debian, this means editing the file /etc/default/tftpd-hpa, and adding   ...
 
Enable SSH on Dell Networking N-series (PowerConnect) switches
edited by on August 21st 2018, at 11:20
To enable SSH on Dell Networking N-series (formerly known as Dell PowerConnect), you first have to generate the required private RSA and DSA keys. If you don't, you're met with a very secretive error message:

SSH could not be enabled.

To generate the keys, and configure and enable SSH, log on to the switch using the console cable or log on through Telnet:

Go into EXEC mode, then in CONFIG mode:

enableconfigure

Generate both the RSA and DSA keys:

crypto key generate rsacrypto key generate dsa

Now, you can enable the SSH server:

ip ssh server

Optionally: you can also change the default listen port:

ip ssh port 22

With more recent firmware versions, you are no longer able to   ...
 
Revive your old Macbook with MacPostFactor
edited by on August 16th 2018, at 10:13
MacPostfactor is a tool to install Mac OSX 10.8+ on older Macbooks that normally only support up to OSX 10.7 (Lion). It works through a combination of a highly customized installer, a replaced set of drivers and various frameworks, and the original installation app from the App Store. The installation can be done directly on a Macbook already running OSX Lion (so no USB disk required), or on an USB media for installation on another system.

You need an Intel-based Macbook capable of running OSX Lion (10.7) (otherwise your Mac is too old), but one that does not support OSX Mountain Lion (10.8) or higher. PowerPC-based Macs are not supported (they do not run OSX Lion).

The installer app of th  ...
 
Change owner of a SQL Server maintenance plan
edited by on July 12th 2018, at 09:47
When creating a SQL Server maintenance plan, the owner of the plan is set to the user logged in when the plan is created. If another user makes changes, the owner does not change. Sometimes it may become necessary to change the owner (e.g. if the owner's account is being disabled or removed). You can manually change the owner through the SQL Server Agent's Job Activity Monitor but changing it there is only temporary: changes to a maintenance plan will reset the owner back to the original one. Changing the owner from within the maintenance plan is not possible through the GUI, but there is a way to make the change through T-SQL statements.

The following queries need to be run against the msd  ...
 
Managing Office 365 and Exchange Online using Powershell
edited by on July 10th 2018, at 14:46
A few steps to enable management of your Office 365 subscription using Powershell. One uses Powershell because not all configuration is available through the Office 365 Portal, and it's also useful for automation.

Note that the old method of installing the Azure Active Directory Module is deprecated. The only supported way is to install the cmdlets directly through Powershell, as described below.

UPDATE (2018-07-09): removed all deprecated information.

UPDATE (2016-04-20): updated links and information.

Download and install the Microsoft Online Services Sign-In Assistant.

Download and install Windows Management Framework 5.1.

Open an elevated Powershell, and run the following comma  ...
 
Managing Exchange Online using Powershell (deprecated)
edited by on July 9th 2018, at 14:30
You can manage Exchange Online through Powershell in a similar fashion as you would an on-premise Exchange. There are some differences between available cmdlets and what they do between on-premise Exchange and Exchange Online, but the majority are the same.

Using multi-factor authentication
The method mentioned below is deprecated and only works for non-MFA usage. If you are using multi-factor authentication, you will have to use the Exchange Online Remote PowerShell Module to connect to Exchange Online. Instructions can be found in this article.

Using PS remoting, the cmdlets for Exchange Online are imported through the internet, so first, you need to change the Powershell execution polic  ...
 
VMware vConverter: A File I/O Error Occurred while accessing ''
edited by on July 3rd 2018, at 14:58
When using VMware vConverter Standalone 6.1 or newer, performing a P2V may fail very early in the process with the following error:

Error
FAILED: A file I/O error occurred while accessing ''.

You can work around the issue by enabling Use proxy mode on the Destination System page at the conversion wizard. As an alternative workaround, perform the P2V directly to a ESX host.

The reason for the error has to do with the ESX host's certificate not being trusted when performing a P2V to a vCenter.

If the Use proxy mode does not resolve your issue, please check whether the FQDN of the ESX host is resolvable on the machine running vConverter. Even when using strictly IP addresses, the FQDN still  ...
 
Get the actual serial number of a Barracuda NG Firewall
edited by on June 18th 2018, at 12:17

The actual serial number of a Barracuda NG Firewall can be obtained remotely in two ways:

  • Log on locally using NGAdmin and read the serial number from the dashboard. The serial number shown there is the actual serial number, and not the configured serial number.
  • Log on locally using SSH and run hwtool -s will also display the actual serial number.
 
Download older versions of a game on Steam
edited by on May 29th 2018, at 19:11

A very useful guide on how to download specific files (such as older versions of games) on Steam:

https://www.reddit.com/r/Steam/comments/611h5e/guide_how_to_download_older_versions_of_a_game_on/

 
Error 0x8007000d in Task Scheduler on Windows 2003 after sysprep
edited by on May 2nd 2018, at 15:43
After performing actions which causes the SID to change (such as sysprep or a DC promote/demote), when opening an existing task in the task scheduler, you may encounter the following error:

Task Scheduler
General page initialization failed.
The specific error is:
"0x8007000d: The data is invalid." An error has occurredattempting to retrieve task account information.
You may continue editing the task object, but will beunable to change task account information.

As a result, it is also not possible to view or change the account information for the selected task.

To work around the issue, remove a saved RSA key, which has been invalidated with the change:

Stop the Task Scheduler s  ...
 
Trying out Data Domain Virtual Edition
edited by on April 3rd 2018, at 13:38

DellEMC offers a free-to-try virtual appliance of DataDomain, allowing you to do a Try & Buy. You can download the appliance here:

https://www.emc.com/products-solutions/trial-software-download/data-domain-virtual-edition.htm

 
Setting network to Private in Server 2012 R2
edited by on March 22nd 2018, at 16:34
On a fresh install of Windows Server 2012R2, not joined to a domain, the first network connection (obtained through DHCP) is always treated as a Public network. Normally, when joining a domain, the network connection then becomes a Domain network, but if the server will not be joined to a domain, you probably will want to set it to Private. Unfortunately, the Public Network link in Network Center is not clickable, and thus, cannot be changed. But you can make the change anyway through the Local Security Policy.

Through Powershell (preferred method):

Look up the name of the network interface (e.g. "Local Area Connection") in the network adapters list.

Open an elevated Powershell   ...
 
Killing sessions to a compromised Office 365 account
edited by on March 12th 2018, at 12:01

A very useful blog article about killing active sessions to a compromised Office 365 account:

https://blogs.technet.microsoft.com/cloudyhappypeople/2017/10/05/killing-sessions-to-a-compromised-office-365-account/

 
Powershell: colorize output in Format-Table
edited by on March 12th 2018, at 08:27

Starting from Windows 10 Creators Fall Update, you can use VT escape sequences to colorize the output to console. You can use this to colorize columns in Format-Table, too.

A sample snippet, colorizing the output based on the contents of the "Status" field:

$somelist | FT FirstName,LastName,@{l="Status";e={
    switch ($_.Status) {
        "OK" {$color = 92; break}
        "NOT OK" {$color = 91; break}
        default {$color = 93}
    }
    "$e[${color}m$($_.Status)${e}[0m"
}}

A complete list of color codes can be found here: https://docs.microsoft.com/en-us/windows/console/console-virtual-terminal-sequences

 
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