I posted almost two years ago to the day on a cool tool called BIG-IP Config
Visualizer, or BCV, that one of our field engineers put together that
utilizes a BIG-IP config parser and GraphViz to create images visualizing the
relationship of configuration objects for a particular virtual server.
Well, I’m here to report that another community user, Russell Moore, has
taken that work to the next level. Rather than trying to figure out the
nuances of configuration objects amongst all the versions of BIG-IP, he
converted the script to utilize iControl! In this tech tip, I’ll walk
through the installation steps necessary to get this tool off the ground.
Install a few libraries and GraphViz via apt-get
apt-get install libssl-dev libcrypt-ssleay-perl libio-socket-ssl-perl
Open a CPAN shell and install SOAP::Lite and Net::Netmask
BIG-IP LTM supports internal and external classes (called Data Groups in the
GUI) of address, string, and integer types. An internal class is stored in
the bigip.conf file, whereas external classes are split between the
bigip.conf and the file system (the class itself is defined in the bigip.conf
file, but the values of the class are stored in the file system in a location
of your choice, though /var/class is the location defined for synchronization
in the cs.dat file) Which flavor? Depends on the requirements. External
classes are generally best suited for very large dataset... (more)
User Ralph Hoflich dropped an interesting problem off in the forums for his
first post evah…he had a wireshark capture with a highly unusual header
Yes, the header name was “:”. This is interesting as it is also the
separator in headers between the field name/value pair as described in rfc
2616 section 4.2. Thankfully, it’s just another character and is parsed
out as such with iRules. So the simple task of removing a header like this
is completed painlessly (as Ralph suspected in his own question). I added a
couple logging statements to check before/after request heade... (more)
The default logon page for the Access Policy Manager module is pretty basic,
particularly so if only the minimal username and password is configured.
However, APM is wildly flexible. In this tech tip, I’ll cover customizing
the logon page by adding a dropdown box of services to the standard username
and password fields.
Introduction Background Information
The goal here is to provide access to multiple web applications behind APM
through the use of an admin-defined dropdown menu and different LTM pools for
each web application. We will be generating the list dynamically through t... (more)
I got a request yesterday morning to asking if there was a way to drop HTTP
requests if a certain number was referenced in the Accept-Language header.
The user referenced this post on Exploring Binary.
The number, 2.2250738585072012e-308, causes the Java runtime and compiler to
go into an infinite loop when converting it to double-precision binary
floating-point. Not good. Twitter is ablaze on the issue, and there is a
good discussion thread on Hacker News as well. So how do you stop it?
At first, this appeared to be a no-brainer, just copy that string and drop if
found in that... (more)