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Recently I worked on a desktop system that was having issues connecting to WSUS and installing patches. This was a Windows 10 system (upgraded from Win 8.1) with Office 2016 (upgraded from Office 2013). Every time that I opened the Windows Update app, it listed several Office 2013 updates that couldn’t install. You could press the Retry Now button and it would run for a minute or two, but always fail with a non-specific and non-helpful error.

After running through troubleshooting steps of resetting the Windows Update agent, I finally started looking at the Office 2013 aspect. I decided to uninstall whatever 2013 components were still there and reinstall, if necessary. I loaded Programs and Features and Office 2013 was not listed.

I found a Microsoft utility to forcibly uninstall Office 2013/2016 products (link) and ran it on this PC. On the first run (and subsequent reboot), Office 2016 was removed, but 2013 was still detected by the Windows Update agent. On the second run (and subsequent reboot), Windows Update installed all of its normal patches without the Office patches listed.

I reinstalled Office 2016 and was able to bring the computer up to date. It really appears as if the 2016 upgrade didn’t fully remove all of the 2013 components as a part of the upgrade.

 

 

0 Comments   Networking Microsoft Office Windows 10 windows update

 

Due to a recent audit finding, one of our customers requested that only TLS 1.2 be allowed and the cipher security level set to “high” (AES256-SHA256 DHE-RSA-ASE256-SHA256) on their Cisco ASA firewall. The AES256-SHA256 security ciphers are not proposed by Java 8 natively. In order to add the security ciphers, you must perform the steps below.

Directions to setup Java Cryptography Encryption (JCE) Unlimited Strength Jurisdiction Policy:

 

  • On your PC, browse to C:\Program Files (x86)\Java\jre1.8.XXX\lib\security
  • Rename files
    • Rename local_policy.jar to local_policy.jar.OLD
    • Rename US_export_policy.jar to US_export_policy.jar.OLD
  • Go to http://www.oracle.com/technetwork/java/javase/downloads/jce8-download-2133166.html for the following files:
    • Copy local_policy.jar to C:\Program Files (x86)\Java\jre1.8.XXX\lib\security
    • Copy US_export_policy.jar from to C:\Program Files (x86)\Java\jre1.8.XXX\lib\securit
  • Launch ASDM again and the ASA will negotiate to the DHE-RSA-AES256-SHA256 security cipher

 

0 Comments   Networking Java TLS

 

After installing Windows 10 from scratch, I noticed some applications would occasionally need .Net Framework 3.5. If I went to Programs and Features then Windows features to install .Net Framework 3.5, it would ask to download from Windows update which would always fail. I found a KB article at https://support.microsoft.com/en-us/kb/2734782 that indicated I would have to use the Windows 10 installation DVD (or ISO) as the source for the updates. This was accomplished by editing Group Policy on the local system:

Going to Computer Configuration -> Administrative Templates -> System

then enabling Specify settings for optional component installation and component repair

then, in the Alternate source file path, point to the DVD or ISO sources\sxs folder

 

You then need to run the gpupdate /force command then add the .Net Framework 3.5 Windows feature.

0 Comments   Networking Windows 10 .NET Framework

 

Here are two links to articles discussing the NIST and their discouraging of SMS use for multi-factor authentication. The special publication by NIST actually says

If the out of band verification is to be made using a SMS message on a public mobile telephone network, the verifier SHALL verify that the pre-registered telephone number being used is actually associated with a mobile network and not with a VoIP (or other software-based) service. It then sends the SMS message to the pre-registered telephone number. Changing the pre-registered telephone number SHALL NOT be possible without two-factor authentication at the time of the change. OOB using SMS is deprecated, and will no longer be allowed in future releases of this guidance.”

https://techcrunch.com/2016/07/25/nist-declares-the-age-of-sms-based-2-factor-authentication-over/

 

https://www.engadget.com/2016/07/29/sms-two-factor-authentication-isn-t-being-banned/

0 Comments   Networking Security and Compliance two factor authentication SMS

 

We have a backup internet connection that is tied into our Test Lab environment. As a part of this, I needed to change the default gateway on all of my Test Lab VMs so that everything would go out the proper connection. Now, I could RDP into each one and make the change, but that is boring and this is a LAB! It’s time to play a little bit and see if we can change this efficiently.

My initial thought was to use a combination of "psexec" and "netsh" commands to change that IP. I figured out the netsh command necessary to change an IP address (including the default gateway) and just left the IP address information out of the command. Much to my surprise, it set the adapter to DHCP, yet statically configured a default gateway. For our LAB this doesn't work since DHCP doesn't grab an address, but at least now I know. So how do you go about scripting a change to the default gateway for multiple Windows systems?

Use a route add command, of course! Using psexec to push the command out, I ran “route add -p 0.0.0.0 mask 0.0.0.0 10.1.1.1” where 10.1.1.1 is my new default gateway. Much to my surprise, it changed the default gateway entry on the adapter without issue.

0 Comments   Networking networking Windows

 

Since Veritas took over Backup Exec from Symantec, we’ve had issues getting licensing migrated and renewed for various reasons.  

For one customer we had recently renewed maintenance for one year and needed to apply the license to the Backup Exec console. In the console, I could see there were product licenses and maintenance licenses. The maintenance licenses had indeed expired. 

When I went to the Veritas licensing portal to retrieve the licenses, they showed an expiration date in one year from now. I downloaded the new licenses, but no matter what I tried to import or delete existing licenses, it never would display the new maintenance expiration dates.

I called Veritas and they changed the way maintenance licenses are managed from the Veritas portal; they are not managed on the Backup Exec console any longer.  You can ignore the dates for the maintenance contract now since they moved over to Veritas.

0 Comments   Networking Backup Exec licensing Veritas

 

 

When I was upgrading to Windows 10, I decided to install from the Current Branch for Business ISO rather than an in-place upgrade since it'd been more than three years since I'd performed a clean install. Immediately after the Windows 10 install and activation, I decided to enable BitLocker since it seemed like a good idea to do this as early in the process as possible.

After enabling BitLocker and setting a PIN I rebooted and was presented with the BitLocker passcode screen. I entered the code and pressed Enter and the system stayed on the BitLocker screen. After several minutes, I forced power off and then powered the laptop on. The BitLocker screen appeared again with the same results after entering the code. After repeating this cycle several times, I pressed the escape key in order to enter the recovery key. Rather than prompting for a recovery key, the system booted directly into Windows and, after logging in, displayed an error message about C: not being encrypted because the key could not be obtained from the TPM chip.

I tried several things related to UEFI-only boot and UEFI/legacy boot in the laptop startup screens without any success. Every time we changed any boot options on the laptop and then saved and restarted, the system could not find the boot drive until we forced power off. Then, the boot drive could be found.

Finally, I installed Windows patches before trying to enable BitLocker and it worked perfectly.

0 Comments   Networking Windows 10 BitLocker

 

Example Error Message

Delivery has failed to these recipients or groups:

zixvpmgateway@zixvpm.domain.com

A prolem occurred while delivering this message to this email address. Try sending this message again. If the problem continues, please contact your help desk.

The following organization rejected your message: xxxxxx.ess.barracudanetworks.com. 

Overview 

This post is intended to provide a high-level overview of the routing and delivery between two companies who utilize a ZixGateway and the Barracuda Email Security Service to encrypt and scan their messages. In addition, this document will cover a common delivery issue between these same companies. [more]

Prerequisites

  • Both companies have a ZixGateway Email Encryption virtual or physical appliance
  • Both companies use Barracuda Email Security Service for antispam/antimalware scanning
  • The sending company has configured the Barracuda Email Security Service to scan all outbound email

Procedure

When a ZixGateway customer sends an email to another ZixGateway customer, the sending appliance is aware that both customers use Zix encryption and will automatically encrypt the email before delivering it. This is seamless to end users on both sides and makes email delivery between the two automatically secure.

As an email is encrypted, the sending ZixGateway wraps the entire email up as an encrypted attachment and redirects the message to zixvpmgateway@zixvpm.recipientdomain.com. Looking at this email after it has been encryption will only reveal the sender’s email address, the subject line of the message, and the modified recipient’s email address.

At this point, any mail gateway will look up MX records for zixvpm.recipientdomain.com and deliver it normally until the message reaches the destination ZixGateway. This recipient gateway will unwrap the encrypted attachment (i.e. decrypt the email), and deliver it as normal to the original recipient.

 

Because of this, a significant number of ZixGateway and Barracuda customers may set up two sets of MX records like below:
 
;; ANSWER SELECTION:
fabrikam.com. 3600 IN MX 10 d12345a.ess.barracudanetworks.com.
fabrikam.com. 3600 IN MX 20 d12345b.ess.barracudanetworks.com.
 
;; ANSWER SELECTION:
zixvpm.fabrikam.com. 3600 IN MX 20 Zixgateway.fabrikam.com.
 
This method is acceptable and fairly common from a ZixGateway point of view. From the ZixGateway, the appliance is listening to all IP addresses for incoming email, but if the incoming email is not encrypted, it will be silently dropped. This protects the ZixGateway from being overrun by spam and malicious attempts. Plus, there's no reason to send the encrypted email through a spam filter - Barracuda is unable to see inside the encrypted attachment.
 
The Barracuda Email Security Service utilizes a feature to improve the efficiency of mail routing inside their network. For mail sent between two BESS customers, instead of performing an MX record lookup for every email that passes through their system, they perform an internal lookup inside their customer database and deliver it according to the settings there. In addition, if a subdomain doesn't exist under the account, BESS will look up the root domain for delivery settings.
 
This means that in the case of the example above, mail will bypass the ZixGateway entirely, because BESS will intercept the message and deliver it to the fabrikam.com domain setting. At this point, the internal mail server will reject the message as undeliverable.
 
 
 

 
Workaround
 
The solution to this problem is a simple workaround for the recipient domain. Inside Barracuda, set up a new domain for the zixvpm.domain.com subdomain that delivers to the ZixGateway and add the zixvpmgateway@zixvpm.domain.com user to that subdomain.
 
However if outbound email routing does not flow through Barracuda and SPF is enabled on the email domain, you will need to add the Zix hostnames to the SPF exempt list.
 
Despite Barracuda not being able to scan the encrypted email, this ensures that mail delivered between BESS customers reaches its intended destination while not altering mail flow for all other email traffic. 

0 Comments   Networking Email Barracuda ZixGateway

 

 

One of our customers is using an MPLS network for their WAN connections. but they have installed backup Internet connections at their branch locations in order to maintain connectivity to the corporate office if one of the MPLS connections was to fail. See the diagram below for reference:

In order to configure the backup VPN, a VPN tunnel must be built between the main location and the branch location, in this case Router2 and Router3, respectively. Also, GRE tunnels were built between these routers so that routes could be dynamically exchanged using EIGRP, which also requires adding static routes for the GRE tunnel interfaces to route this traffic out the Internet connections instead of over the MPLS connection. All routers participate in the same EIGRP process. BGP and EIGRP are redistributed into each other on Router1. The EIGRP routes will not be preferred on the branch router (Router3) because EIGRP has a higher administrative distance (90) than BGP (20) and the BGP routes will be used. On the Internet VPN router (Router2), these routes will be preferred because EIGRP internal has a lower administrative distance (90) than external EIGRP (170). This behavior can be changed by adding the  “distance eigrp DesiredInternalAdminstrativeDistance DesiredExternalAdminitrativeDistance” (“distance eigrp 90 80” in this case) command to the EIGRP configuration.

This setup will work for failover, but will additional configuration is needed for the router to automatically failback to the MPLS connection. If the failure is at Router3, Router3 will return to using BGP routes from MPLS when the connection is restored. By default, Router1 will continue to use the routes obtained via EIGRP because the weight of these injected routes of 32768 is greater than the default weight of 0 for learned routes. This can be resolved by setting the learned routes from the BGP neighbor (ISP) to a higher weight than the injected routes. In this case, “neighbor NeighborIPAddress weight 35000” was added to the BGP configuration on Router1. These higher weight routes overwrite the injected routes. 

 The combination of changing the administrative distance in EIGRP and BGP neighbor weights allows this connection to fail to the Internet VPN and return to the MPLS connection dynamically.

0 Comments   Networking MPLS WAN Cisco routers

 

Often times, we come across a physical or virtual machine that has multiple drives on the same disk. It is common that the left partition is the C drive and it has run out of space, or we want the drives separated when we convert the machine from a physical machine to a virtual machine so that we have more flexibility.

Using the VMWare vCenter Converter, we can split the disks to separate VMDK files. This can be achieved when converting the machine from a physical machine to a virtual machine or a virtual machine to a new virtual machine.

  • On the Options page, click Edit in the "Data to copy" section
  • Click Advanced
  • Click Destination Layout
  • Suggest changing the drives to "Thin"
  • Click "Add disk", select the disk you want to split, and click "Move down" until it is listed under the new disk
  • Complete the job wizard and run the conversion job

0 Comments   Networking VMware Converter