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Re: SoC: Improve syslogd



I thought a bit about the approach, I think there is a race condition
in it, even if it works. Quick summary here:
http://blog.gerhards.net/2008/05/more-reliability-for-tcp-syslog.html

Rainer

On Thu, May 29, 2008 at 9:02 AM, Rainer Gerhards 
<rgerhards%gmail.com@localhost> wrote:
> So far just one reply, the others follow (but I need to leave soon
> until later ;)):
>
> On Thu, May 29, 2008 at 1:45 AM, Martin Schütte 
> <info%mschuette.name@localhost> wrote:
>>> this can lead to massive data loss, even to complete data loss. Note
>>> that this is not a direct cause of transport-tls, but of the underlying
>>> plain TCP syslog protocol. I have more details in my blog post on the
>>> unreliability of TCP syslog.
>>
>> I also thought about that message loss and I think I found a solution.
>> Please take a look at
>> http://mschuette.name/wp/2008/05/29/reliable-tcp-reconnect-made-easy/ and
>> let me know what you think.
>
> I think this is a nice but partial solution. Note: I did not yet prove
> what I am talking about ;), but.. As of my understanding of TCP, this
> does not (actually MUST not) work if the connection really breaks
> (that is remote machine or network connection dies). In this case, you
> do not have a real shutdown.
>
> For the TLS use case, however, this should be sufficient (as we always
> have a connection close, at least if nothing goes strangly wrong).
>
> But the shutdown case should work. I'll give it a try and report back.
>
> Thanks for the good idea!
>
> Rainer
>


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