Last update: January 11th 2022 This one is outdated, as the Citrix ADC Version and MAS (former name of ADM) it refers to, is available no more. However, I wrote a new blog on how to enlarge disk space on a Citrix ADC / NetScaler VPX. My NetScaler VPX ran out of disk space. I did several tricks like adding a second disk and mounting ít into the update directors, to be able to upgrade my NetScaler...
last update: October 22nd 2021 Citrix NetScaler Logging and policy troubleshooting Some times it’s quite hard to understand what’s going on. There is a lot of mystics about policies. And it’s even harder to understand what went on (past tense). “Johannes, there had been several problems connecting to <any blabla application here>” “I’m sorry, I...
Why do I love HDX on UDP in Citrix XenDesktop and XenApp? (HDX Enlightened Data Transport EDT) Well, I’m mainly a network guy. So I’ll take a look at this brand new feature from networking perspective.I’ll start from scratch, so I don’t assume you understand network protocols. But let me tell you a joke about UDP first: I got a short joke about UDP, and I don’t care...
Yesterday I published a blog about DDOS- protection. I used the Citrix NetScaler AppQoE feature to do so. That’s nice, but not enough. I still could beat my server to a pulp easily. Just 10 clients launching a DDOS attack using HULK had been enough. I can’t throttle down the number of users to just 10! WTF? Basically AppQoE will just limit the number of users (actually it’s the...
last update: February 21st 2018 How to protect a website using Citrix NetScaler? Well it seems to be easy. A nonsense question. We may use AppQoE (Application level Quality of Experience), a feature introduced with NetScaler version 10, so it’s quite an old feature. Let’s start. AppQoE is enterprise edition My first starting point was E-Docs. Let’s be honest: the guy in charge...
This article is a very first answer to a question I recently received. The question was: You’re talking about web application firewalls. I’d like to know how to use the WAF for reverse proxying. … I also might use a firewall as it also contains functions like SQL injection prevention. So what’s in a web application firewall? A web application firewall, also known as WAF...
I recently was hired to create a web application firewall (WAF) using Citrix NetScaler to protect a SAP Hybris based e-shop. This shop has content for several languages, so we had to select the right home page. The base URL of the website was like that: . SSL was optional. I wanted to set the default language based on browser settings. I based it on HTTP- Header Accept-Language. There are...
Citrix had been cloud computing ever since. In fact, Citrix started doing professional Cloud Computing in 1995. They improved their private cloud approach in 2002 by launching Secure Gateway (and all it’s successors). They already did cloud computing when no one even knew about cloud computing. Maybe Citrix is the cloudiest company on the globe. Citrix dramatically improved their product over...
This is multi langage: a mix of German and English. Look for the flag you prefer .. Kürzlich haben mich Kollegen gefragt, welche Bücher es im Citrix Umfeld gibt. Ich persönlich gehe lieber in einen Kurs, als dass ich Bücher lese, aber Kurse sind teurer, und nicht jeder lernt auf diese Art gleich gut. Ich besitze naturgemäß einige XenApp und XenDesktop- Bücher, nicht alle sind gleich gut. Ich habe...
I’m just setting up a Web Application Firewall on a Citrix NetScaler 11.1 for a costumer’s shop. My costumer mandated: most of the website has to be available via HTTP. However we don’t want to expose sensitive information to the internet, so we had to create a policy redirecting users to SSL whenever needed. So how can we do this? First of all, I had to find out: which...