Posts Categorized: Security

During an implementation project I found myself in a situation where authentication on my ADFS environment failed, due to the impossibility to perform CRL checking. At that moment we didn’t have access to the outbound proxy yet, so I had to temporarily disable CRL checking for the relying parties. I used the following commands:

Every now and then it’s necessary to actually look into a SSL stream between client and NetScaler to inspect what’s actually happening. I struggled with this topic quite a bit, and documentation (eg. From Citrix) is not always complete. I will not pretend this document covers all, but I had some good successes decrypting traces with the following procedure. If you have any additions please let me know, and I will be happy to add them to this post.

I replaced my internal CA and needed to replace all certificates, including the machine certs on my server core machines. I had to replace the domain controller certs, and some machine certs.

This article is mainly for my internal documentation (In case it ever happens again 🙂 ) I had some file system issues with my PFSense SG-8860 (which is a very cool firewall).
After a power outage it went in a reboot loop. I had to connect with the USB console cable and then I fixed it with the following commands:

/sbin/fsck -y /

Run it repeatedly until it no longer reports any errors, at least 3 times. Then reboot with:

/sbin/reboot

So this is one of those topics why I actually started this blog. I’m preparing our environment for a big upgrade off all Citrix Receivers, implement Storefront and decommission our last two webinterface servers. A nice job which already gave me quite a headache. So in this tut I will try to give you the complete tutorial how to implement NSGW with Storefront so the Receiver can actually SSO, and all traffic is routed through the NetScaler Gateway.

I’m testing a little bit with one of my Terminal Servers and noticed I could not connect through RDP with a normal (non-admin) user. Admin users fine but normal users were terminated immediately. I reviewed all settings for a while but couldn’t find the issue. Eventlog gave me a nice warning:

The Desktop Window Manager has exited with code (0xd00002fe)

So this is kind of nerdy but it’s also very cool. And poorly documented, so it’s nice figuring it out. Keeps me off the street 🙂 It is possible to use Google Authenticator as a second factor to authenticate to your NetScaler. And it’s not really hard to implement as well. So if you read Citrix’s blog about it you will see they’re using OpenOTP. The rest of the document is incomplete and give you very little instructions how to install. I will try to write a complete tutorial on how you can acchieve it. Let’s go!

Momentarily I’m working a lot with NetScaler and SHA256 certificates. I noticed that with the change to SHA256 certs the NetScaler has some difficulties importing. The error you get is: Invalid private key, or PEM pass phrase required for this private key.

At this moment I’m using this command a lot so I thought it would come in handy to write a seperate article about it (easier to find). The command you use to convert a private key to PEM format is……..

In this tutorial I’ll guide you in securing your management page. The goal of the tut. is making sure the NetScaler Management Page is SSL encrypted and AD Integrated. Meaning you’re able to login with your Active Directory admin account. Let’s go!