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On Thu, 04 Dec 2014 09:37:24 -0800 Christopher Head wrote: |
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> On December 4, 2014 8:12:58 AM PST, Andrew Savchenko <bircoph@g.o> wrote: |
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> > |
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> >Yes. But booting as much services as possible is even more |
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> >preferable, especially when box is remote. |
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> |
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> Are you sure booting most, but not all, services in a loop is |
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> always better than booting none of them at all? |
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If we're talking about early loop solver, then yes. Because this |
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solver never breaks "need" dependencies. |
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> What if I have an insecure dæmon listening on TCP, I need it |
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> running, but I want to ensure only local processes can connect to |
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> it? Obviously, I would make it “need iptables”, assuming the dæmon |
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> doesn’t have its own bind address config knob. |
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And "need iptables" will do the job. Either weaker part in the loop |
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will be broken, or your loop will be left unsolved (e.g. if |
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iptables directly or indirectly _needs_ your daemon). |
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> What if now, by some accident, iptables ends up in a loop (maybe |
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> not even a loop including $insecure_service, but some other loop |
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> entirely), and it’s the randomly chosen victim? Is it still good to |
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> boot as many services as possible? |
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Yes, it is, because only weak dependencies like "after" and "use" |
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may be broken (and after is considered stronger than use IIRC). |
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As for later loop detector, it may break need dependency. Current |
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need dependency for iptables is fsck <- localmount <- iptables, so |
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it is still unlikely that your daemon will be caught in such |
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need-only loop. Though on author's request later loop solver is out |
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of scope of this discussion now... |
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Best regards, |
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Andrew Savchenko |
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