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On 12/20/05, Kalin KOZHUHAROV <kalin@××××××××.net> wrote: |
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> Eric Brown wrote: |
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> > It's not just init scripts that are designed poorly, it's applications |
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> > that fail to daemonize and dont' return non-zero. (like apache-1.3, |
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> > ntp-date, snort, etc.. most servers). |
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> Yeah, that is the real problem, but that is not fixable immediately. |
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> |
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> > I think the new baselayout has some adjustable sleep/checks on by |
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> > default, but I haven't tries it yet. I suppose that would work by |
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> > having the init script sleep for a short time, then check to see if a |
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> > certain process is running (a dirty hack that's frowned updon by |
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> > some)... |
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> > |
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> > Anyway, I really think this is something worth looking into, either as |
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> > a separate package that implements some kind of monitoring functions |
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> > in init scripts, or as a basic set of monitoring functions that are |
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> > included in baselayout for developers to optionally use. |
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> |
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> > While there are options like daemontools and rmon? I don't think they |
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> > provide a very robust solution to this problem. |
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> Can you elaborate on this? What is wrong with daemontools? |
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> |
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> http://cr.yp.to/daemontools/faq/create.html#why |
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> |
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> > Here's an idea: |
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> > |
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> > Have users emerge a program that can do some basic things: |
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> emerge daemontools |
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> |
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> |
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> > 1) check config scripts of running services for variables like: |
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> > CHECK_COMMAND |
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> svstat /service/daemon |
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> |
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> > SLEEP_TIME |
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> If I get you right, this is hard coded to 1 second for supervise. |
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> |
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> > INIT_SLEEP |
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> If I get you right, this is hard coded to 1 second for supervise. |
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> |
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> > IF_DOWN_DO_THIS |
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> Not sure how important is this, but flexibility can be achieved inside the ./run script of the |
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> daemon. The normal thing is to start it again. |
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> svc -u /service/daemon |
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> |
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> > (those variables could optionally be implemented per package, or |
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> > explicitly disabled, they would have sane defaults in a central .conf |
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> > file for this enhancement package) |
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> This can be worked on, the start is sys-process/daemontools-scripts. |
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> |
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> > 2) is a cron job/daemon that automatically checks all running apps in |
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> > the current runlevel, can report problems (send emails, log stuff, |
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> > etc), can send heartbeat, etc.. |
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> Can you trust cron, started from a init script? |
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> Instead a script started under supervise, as simple as this: |
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> #!/bin/bash |
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> |
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> sleep 60; |
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> `svstat /service/* |grep down >/dev/null` && \ |
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> echo "Something is wrong" | your_favourite_mailer_here |
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> |
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> (The above is not tested, just thought of. Feel free to improve). |
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> (Like there can be intentionally down-ed services -e /service/daemon/down) |
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> |
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> > 3) is well documented in the gentoo handbook since it's probably a |
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> > vital component |
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> http://cr.yp.to/daemontools.html is a good start, in can be improved for sure. |
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> |
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> > To me this kind of thing is probably simple, unixish, and robust |
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> > enough for most of our needs... |
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> > |
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> > Any thoughs? |
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> Don't top-post :-) |
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> |
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> Kalin. |
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> /known also as Korokoro or tar/ |
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> |
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> P.S. Whose MTA changes the subject with [OBORONA-SPAM] ? Please remove that; use a custom header |
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> instead. |
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> |
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> -- |
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> |[ ~~~~~~~~~~~~~~~~~~~~~~ ]| |
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> +-> http://ThinRope.net/ <-+ |
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> |[ ______________________ ]| |
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> |
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> -- |
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> gentoo-server@g.o mailing list |
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> |
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> |
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|
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What I don't like about daemontools is that I like our current init |
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system, and daemontools just totally replaces it. With a little |
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effort, it might be possible to simply supplement the init script |
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resources we already have. I would really miss some of the stuff the |
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gentoo devs made easy for us: automatic dependency handling, ease of |
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use w/rc-update, simple configuration symatics for a wide range of |
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daemons (network stuff and drive mounting stuff)... |
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|
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Anyway, I'm glad you brought up daemontools, there's a lot to learn |
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from it. Maybe approaching this problem from the other direction |
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would even be a good idea: How can we enhance daemontools to create a |
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new gentoo init script system that's every bit as friendly as the |
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current one? |
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|
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-- |
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