Tag Archives: NetScaler

AAA-default settings changed with Citrix ADC (NetScaler) 13 built 41.20

Yesterday I upgraded to NetScaler 13 built 41.20. Everything worked fine. No problems. But out of a sudden, my Exchange deployment failed to authenticate (I did it following Julian Mooren’s outstanding deployment guide). I did some further investigation and found all my other AAA servers don’t authenticate, even though the… Read more »

Citrix ADC / NetScaler: two factors from outside, single factor inside

last update: September 25th 2019 I was recently asked: Johannes, is it possible to orun the same AAA server, from the inside with single factor, from the outside with two factor authentication? Of course it is. That’s how you do: Prerequisites My test environment contains of a lb vServer (lb_vsrv_colors)…. Read more »

Citrix ADC (NetScaler) 13: Pre-authenticating to TCP services

photo by geralt (pixabay.com) Recently I had to find a solution to block all connections to a TCP based service (SSH, TCP port 22), except of connections from IP addresses that pr-eauthenticated using a AAA vServer. This is something, most firewalls can do, but a Citrix ADC / NetScaler can’t…. Read more »

How will a Citrix ADC (NetScaler) Web-application Firewall (WAF) change your ADC’s behaviour?

There is one thing different about a Citrix ADC WAF (Web Application Firewall) compared to most other features in Citrix ADC: It will affect your whole ADC deployment as soon as you turn it on. It you would, for example, turn on rewriting feature (enable feature RW), it would probably… Read more »

Detecting Slowloris with Citrix NetScaler (Citrix ADC)

Last update: Nov 21th, 2018 tested using firmware 11.1 If you read about slowloris, you always read about NetScaler doing a great job. Tests in our lab environment show: NetScaler will successfully block these attacks. And there is hardly anything we have to do about it: It’s built into the… Read more »

Concerns about Citrix NetScaler Web Application Firewall (WAF)

Let’s talk about a WAF, a Web Application Firewall on a Citrix NetScaler. What’s to be concerned off? Is it worth while considering a NetScaler to be your WAF? I do work for several companies, including Citrix Consulting Services. Recently I worked on some Web Application Firewall projects, so I… Read more »