Bazsi's Home Automation blog

This was first posted as a comment under an article on lwn.net, but I thought it was important enough to post it here for others not reading lwn. Please go ahead and read the original article which is about the "Open Core" business model and its problems from the Free Software community point of view. A commenter thought that syslog-ng was an example, which only exists as a marketing tool for the company's commercial offering. Anyway, here's my post: First of all, I want to make it clear that I'm biased on the syslog-ng case, but still wanted to express my opinion here. I'm biased as I'm the primary author of syslog-ng. I think syslog-ng is a completely different case from the one described by Neary. The GPL version is not crippleware, it was never published for marketing purposes only and for the majority of syslog-ng's existence only the Open Source stuff existed. The Premium Edition is only about 3 years old and syslog-ng started in 1998. W...

I've just uploaded syslog-ng 3.2alpha2 to the release directory . The last alpha release didn't compile on all supported platforms and the automatic test-suite was disabled, because it only worked if syslog-ng got installed first. These obstacles have been overcome and together with some fixes and a couple of new features, 3.2alpha2 is now available. I've also forward ported all bugfixes from syslog-ng 3.1.2. For those who are starting to experiment with the 3.2 branch, here's the list of new features compared to 3.1. Those who tried 3.2alpha1, the list of changes compared to 3.2alpha1 is at the end of this post. Since the documentation of syslog-ng is not yet up-to-date with the new features introduced, I've tried to also include URLs for the best known descriptions. The references may not be 100% accurate, but should give anyone interested an idea how to start experimenting. Also, please note that although this is an alpha release, the bulk of the changes are in t...

I was giving a lot of thought recently to the topic of naming name-value pairs in syslog-ng. Until now the only documented rule is stating somewhat vaguely that whenever you use a parser you should choose a name that has at least one dot in it, and this dot must not be the initial character. This means that names like MSG or .SDATA.meta.sequenceId are reserved for syslog-ng, and APACHE.CLIENT_IP is reserved for users. However things became more complex with syslog-ng OSE 3.2. Let's see what sources generate name-value pairs: traditional macros (e.g. $DATE); these are not name-value pairs per-se, but behave much like them, except that they are read-only syslog message fields (e.g. $MSG) if the message is coming from a syslog source filters whenever the 'store-matches' flag is set and the regexp contains groups rewrite rules, whenever the rewrite rule specifies a thus far unknown name-value pair, e.g. set("something" value("name-value.pair")); and of cour...

syslog-ng 1.6.x and 2.0.x versions had lived quite long. A lot of distributions used these versions and never upgraded to the newer ones. This has changed recently, Peter Czanik was busy to help maintainers get to the latest versions. Already available in the latest release: openSUSE FreeBSD ports Mandriva Gentoo portage OpenBSD ports In development branches: Debian Ubuntu Fedora These all carry 3.1.1, which is quite recent (and a successful release too). There are some fixes accumulated in the git tree though, so I hope to get 3.1.2 out of the door soon.

In one of my previous posts , I've mentioned that syslog-ng is not for syslog anymore, we aim to support other log formats too, preferably those that have some kind of structure. In fact syslog-ng is trying to convert all incoming messages (be them unstructured syslog messages, process accounting messages or SNMP traps) into the same, common format: name-value pairs tag or tags that connects the event to one of the patterndb schemas This information coming in from different sources can be stored and processed with the same infrastructure. Correllation between SNMP traps and syslog messages or netflow records should be possible. I probably don't need to mention, that we use patterndb to extract information from syslog messages. But structured information sources contain name-value pairs in the first place, so why not use them natively? This is what the experimental process accounting feature of syslog-ng demonstrates. With this module, syslog-ng is able to read the process accou...

I thought I'd post a quick update on the patterndb project status. Our first aim was to draft a basic policy which governs how patterns should be created. This is available in the patterndb git repository as a README.txt file. Although not completely finished, I feel the current description is enough for some basic work to start, to gather more experience. Here is the current version: http://git.balabit.hu/?p=bazsi/syslog-ng-patterndb.git;a=blob;f=README.txt;hb=HEAD Also, after discussing the policy we've set a target to cover login/logout events from all parts of a generic Linux system. Currently sshd is quite nicely covered, su is coming along and I still have some submitted log samples that need marking up. With the sshd/su patterns a quite nice percentage of my "auth.log" file is covered and using pdbtool " grep on steroids " feature, the marked up patterns are already quite useful. Further log samples and a hand in helping me out to mark up the patterns...

You may have heard of my last project to collect log samples from various applications, in order to convert log data from free-form human readable strings into structured information. The first round to collect login/logout messages from sshd is now complete. You could ask: ok, but what is the immediate benefit? You supposedly have a lot of unprocessed log files, and syslog-ng's db-parser() has not been used to process them, thus they are stored as good-old plain text files. I spent a couple of hours to add a "grep"-like functionality to pdbtool which makes it easy to process already existing log files, giving you immediate benefit for each and every sample added to patterndb. For example, if you are interested in login failure events, you could say: zcat logfile.gz | pdbtool match -p access/sshd.pdb \ --file - \ --filter 'tags("usracct") and match('REJECT' type(string) value("secevt.verdict"));' \ --template '${usracct...

Starting with syslog-ng OSE 3.2, syslog-ng became plugin based, which has some consequences that even experienced syslog-ng users may stumble into. The most obvious one, is that syslog-ng now produces a series of .so files loaded at runtime, instead of being a monolithic executable. If a given .so is not not or not loaded, some of the functionality may be missing. This usually manifests itself by a syntax error when parsing the configuration file. Second: if you compile syslog-ng from source, the unit/functional test programs also want to load plugins, and they try to do that from the install directory. This means that you first have to install syslog-ng using "make install" before running the testsuite. This is not an ideal solution, but should work for now. Plugins are loaded from $prefix/lib/syslog-ng by default, however this can be changed using the `module-path` global, which contains the list of directories where syslog-ng should look for modules. You can change this us...

syslog-ng has been around for about 12 years now, but I think the biggest change in the project's life is imminent: with the upcoming release of syslog-ng OSE 3.2, syslog-ng will become an independent entity. Until now, syslog-ng was primarily maintained & developed by BalaBit, copyrights needed to be reassigned in order to grant BalaBit special privileges. BalaBit used her privileges to create a dual-licensed fork of syslog-ng, named "syslog-ng Premium Edition". The value we offer over the Open Source Edition of syslog-ng are things that larger enterprises require: support on a large number of UNIX platforms (27 as of 3.1), smaller and larger feature differences (like the encrypted/digitally signed logfile feature) better test coverage and release management longer term support Although perfectly legal, this business model was not welcome in various Free Software communities, and has caused friction and harm, because BalaBit has enjoyed a privilege that no others cou...

By now probably most of you know about patterndb, a powerful framework in syslog-ng that lets you extract structured information from log messages and perform classification at a high speed: http://www.balabit.com/dl/html/syslog-ng-ose-v3.1-guide-admin-en.html/concepts_pattern_databases.html Until now, syslog-ng offered the feature, but no release-quality patterns were produced by the syslog-ng developers. Some samples based on the logcheck database were created, but otherwise every syslog-ng user had to create her samples manually, possibly repeating work performed by others. Since this calls out to be a community project, I'm hereby starting one. Goals Create release-quality pattern databases that can simply be deployed to an existing syslog-ng installation. The goal of the patterns is to extract structured information from the free-form syslog messages, e.g. create name-value pairs based on the syslog message. Since the key factor when doing something like this is the naming of ...

I've just commited a small incompatible change for syslog-ng 3.1, even though theoreticaly I shouldn't have. The change is not big, simply the 'store-legacy-msghdr' flag became default for all sources, whereas earlier you had to specify that explicitly. In order to understand why I did that, a short description of the flag follows below. syslog-ng processes all incoming messages into fields (things like $PROGRAM and $DATE) and then reconstructs the message based on this parsed information when it has to write the message to a file. Before syslog-ng 3.0 a message was split into the macros: "$DATE $HOST $MSG", which expanded to the actual log message. "$MSG" above was expanded to a line like: "program[pid]: message" With syslog-ng 3.0 and the integrated handling of RFC5424 and RFC3164 this format was changed and an $MSGHDR macro was created for the "program[pid]: " part and I got rid of this part from $MSG. (of course if you are run...

I've just pushed a round of updates to the syslog-ng 3.2 repository, featuring some interesting stuff, such as: SQL reorganization: Patrick Hemmer sent in a patch to implement explicit transaction support instead of the previous auto-commit mode used by syslog-ng. I threw in some fixes and refactored the code somewhat. Configuration parser changes: the syntax errors produced by syslog-ng became much more user-friendly: not only the column is displayed, but also the erroneous line is printed and the error location is also highlighted. Additional plugin modules were created: afsql for the SQL destination, and afstreams for Solaris STREAMS devices. Creating a new plugin from core code takes about 15 minutes. I'm quite satisfied. With the addition of these two modules, it is now possible to use syslog-ng without any kind of runtime dependency except libc. The already existing afsocket module (providing tcp/udp sources & destinations) is compiled twice: once with and once withou...

The SQL destination in syslog-ng so far assumed that databases automatically start a new transaction for each INSERT statement that syslog-ng issues. This works fine, however there is a significant overhead of starting new transactions, with sqlite I've measured about 20 times performance increase on my development notebook and my debug build. With explicit-commits: bazsi@bzorp:~/.zwa/install/syslog-ng-ose-3.2$ loggen -x -r 1000000 -I 10 -S log average rate = 9377.28 msg/sec, count=93776, time=10.003, msg size=256, bandwidth=2344.32 kB/sec With per-statement (automatic) commits: bazsi@bzorp:~/.zwa/install/syslog-ng-ose-3.2$ loggen -x -r 1000000 -I 10 -S log average rate = 529.46 msg/sec, count=5299, time=10.083, msg size=256, bandwidth=132.36 kB/sec So this really seem to matter. In order to configure it you can use the following options in an SQL destination: flush_lines/flush_timeout controls how much messages get into the same transaction, similar to what these parameters mean f...

After last the stable syslog-ng 3.1.0 release last week, I've opened the 3.2 branch to receive the new stuff. The first bits are already in the repository: the basic plugin framework and the conversion of the socket related stuff (tcp, udp, unix-dgram, unix-stream, syslog drivers) into a separate plugin. The reason of the afsocket plugin conversion is to help moving the OpenSSL dependency to a separate package in distributions where this dependency cannot be associated with core packages like syslog-ng. But I see a lot of potential behind the plugin framework, and I still have a lot of ideas, just check my last blog post in the topic . Also, there's an even more experimental feature in the "blocks" branch right now, it is still incomplete, the naming and the syntax is still vague. The aim is there to provide syslog-ng.conf C++ template-like functionality in order to make the configuration easier by using pre-configured config snippets. For example: block source tomca...

I'm proud to announce that both the Open Source and the Premium editions of syslog-ng 3.1 was published and are available on our website. This is an important milestone in multiple ways: the new feature/stable release schema is making its debut the patterndb got significant improvements: new parsers, pdbtool, tagging support the ability to change/add RFC5424 style structured data to messages even more supported platforms (Tru64 on alpha, HP-UX 11iv2 on Itanium and older Linux versions) the diverging developments of syslog-ng Open Source Edition, Premium Edition and syslog-ng Store Box was merged into a new base, Some interesting (ok, for us developers :) statistics follow: Premium Edition: 586 commits 200 files changed, 23479 insertions(+), 5513 deletions(-) Open Source Edition: 189 commits 115 files changed, 9020 insertions(+), 3225 deletions(-) The reason for the big difference is the merger of the currently propriatery log indexer engine used in SSB into the current Premium Edi...

Since the last post, I could hack a couple of hours on the plugins branch, which now compiles. The plugin framework is capable for supporting a quite important core functionality: all socket like sources/destinations are now found in an external plugin called "afsocket". The reason I've started with afsocket is to make syslog-ng a bit less dependant on OpenSSL. A couple of distributions didn't include syslog-ng 3.0 in their current releases, because it uses OpenSSL from /usr, while syslog-ng should remain in the root directory. By separating afsocket from the syslog-ng core, I can compile afsocket with and without TLS support, which can be put into separate packages. Thus syslog-ng can operate without OpenSSL. And the same plugin framework will enable me to create a wide variety of plugins. My ideas: Plugins for all syslog-ng components (source, destination, filter, rewrite, parser) Python scriptability (a simple correllation engine in Python?) macro transformation fu...

Things have been a little rough last couple of months, that's why I haven't posted here. I'm in a rush right now as well, but I just wanted to let you know that I have started working on modularizing syslog-ng. It is only a preliminary prototype, and as of now it doesn't compile, but the way it's going to work is already visible: each plugin will have its own plugin and with some trickery the large syslog-ng.conf parser will call out to the plugin parser. The user will recognize such a plugin as an integral part of syslog-ng. E.g. this is a sample configuration file: @version: 3.0 @module: dummy ... destination d_dummy { dummy(dummy_opt(yes)); }; ... See the dummy plugin code in my git repository, in the "plugins" branch. Please note that that branch is going to be rebased a couple of times yet, I've released it in the spirit of "release early, release often". I hope to get some of the recent contributions into plugins, instead of bloating th...