Citrix Command Center Cipher Suites

I recently installed and configured Citrix Command Center on a client to monitor and configure their NetScaler appliances.

When I opened the management page with Chrome, I got a message that the server was using a weak DH public key.

Since the guys didn't seem to be very helpful with issuing a certificate from their CA, I decided to disable the Diffie-Hellman cipher suites used by Command Center as a workaround.

To do that, you have to edit some apache configuration files.

The first step is to stop the Command Center service. Then make a backup copy of the following files:
1. CommandCenterInstallDirectory\apache\tomcat\conf\backup\server.xml
2. CommandCenterInstallDirectory\conf\transportProvider.conf

Search the server.xml file for "ciphers" to get to the part where the cipher suites are defined and then remove all the DH ciphers.
 
Set the same ciphers on the <CipherSuites></CipherSuites> part of the transportProvider.conf file.

Start the Command Center service and everything should be OK.

This is only a work around to get things going, not a solution. You should replace the certificate with a certificate from your CA to provide efficient security.

Popular posts from this blog

Domain Controller Machine Password Reset

Image
On my lab environment, I've configured two Active Directory sites since most enterprises have offices in more that one places. My lab however is not running 24/7 and the domain controllers in the second site are rarely turned on in order to save resources. This leads to issues with the Active Directory replication such as the "The target principal name is incorrect" error when I execute:  repadmin /syncall /AdeP. To remedy the issue, we have to reset the machine password of the domain controller that has been offline. First off, we are going to stop and disable the Kerberos Key Distribution Center (kdc) service on the problematic domain controller, in our case DC4. There may be some tickets in the cache so we should also clear them using klist purge Now it's time to change the machine password of the domain controller using the command netdom resetpwd /s:dc3 /ud:lab\administrator /pd:* Replace the "lab\administrator" with an account on your
Keep reading

Configuring a Certificate on Exchange Receive Connector

Today's article is about configuring Exchange receive connectors with specific certificates. Out of the box, Exchange uses self signed certificates to provide TLS secured mail flow. This will definitely be an issue if you expose the SMTP protocol to client computers since they won't trust the certificate. In this article we are going to configure a certificate that was issued by a third part authority to the Client Frontend receive connector. We'll start with getting the thumbprint of the certificate using the Get-ExchangeCertificate cmdlet: [PS] C:\> Get-ExchangeCertificate Thumbprint                               Subject ----------                               ------- 241B864DC82C664FECBA18B8D54987AAFB65B4C2 CN=*.lab.com, ... D4D210886B34E690191A1F008C78FDD0E7325DD4 CN=Exchange2013A 960171662EB261162F9C8CBE12E0B75D6F06ABB0 CN=Microsoft Exchange Server Auth Certificate 2690324B827A9F2B75D59104F81CAAA57CDD627B CN=WMSvc-Exchange2013A [PS]
Keep reading

Running Multiple NGINX Ingress Controllers in AKS

Image
In some of the previous articles of this blog, we went through the process of installing NGINX as the Ingress Controller in AKS clusters. Either for applications that should be available directly from the public internet, or for applications that should only be accessed from networks considered internal. In the majority of the cases, however, and given that an AKS cluster is an environment that is designed to host multiple applications and provide economy at scale, additional ingress controllers may be required. In this post, we're going to go through the process of deploying an additional NGINX ingress controller that is going to be used for internal applications. The below diagram depicts the desired outcome: The Angular application is published via the public NGINX through the Azure Load Balancer that has been assigned a public IP. The .NET app is published by a different set of NGINX pods that are deployed in a different namespace and their ingress controller service is connect
Keep reading