Friday, March 06, 2009

rsyslog and solaris

This week, I had the opportunity to work a bit on rsyslog on Solaris. Most importantly, I could set up a compile and test environment (*not* that easy if you don't know your way around Solaris...) and have integrated those patches that folks have sent over time (unfortunately I have lost many of the contributor names, so if you are among them please let me know for proper credits!).

I was able to integrate those patches and make sure that they don't break the linux build (I am still a bit in the verification process, but it looks good). I have created a solaris branch in git and will in the future keep solaris-specific additions in that branch. I will merge that branch back into the master branches every time I am confident enough that it doesn't break anything in the main stream build.

I was satisfied to see that not that many changes were required for a Solaris build. So the initial effort, some month ago, seems to have paid well. I have seen that the solaris git branch compiles, but I have not done any serious testing on Solaris. Still, I am short on time and I have to admit I have spent more time on it this week than I should. So testing is off-limits for now...

However, I got some good impression on what it takes to make rsyslog really run on Solaris. First of all, even gcc4 does not provide the atomic instructions that it is used to provide on Linux. This case is not really handled in the code, so the end result is that the binary will be racy. I guess it will run, but it will have subtle issues on high-volume log servers and/or serves that run asynchronous action queues. Especially if the later is used, I'd expect rsyslogd to segfault every now and then (but without async actions it should not be that bad, at least I think).

There also still does no kernel input plugin exist (or an imklog driver). I also guess there may be issues with the local log socket. I'd still caution everybody to be very, very careful when experimenting with the local log socket. I remember earlier testing where rsyslogd simply destroyed the socket but never was able to re-create it. Some other tweaks are probably required to core and runtime files. Some compiler messages point into that direction (and part of that may even be nasty).

I have compiled only the bare essentials, without TLS, database drivers or anything else fancy. I expect some mild to moderate problems with them, too.

So in short, the current code base is probably be used to run a relatively stable syslog relay or file-only receiver. I wouldn't put it in too much production, though. For folks interested in rsyslog on Solaris, we now at least have a version again that can be build and serve as a basis for extension. I am glad I could do that.

As a side-note, I am still looking for sponsors of a full rsyslog Solaris porting effort. If you would like to sponsor (or know someone who does), just mail me and I'll help settle the dirty details ;)

I hope this update - and the progress made - on rsyslog on Solaris is useful for a couple of folks.

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