Garrett Cooper added the comment:

The code doesn't appear to be conforming to RFC-3164 or RFC-5424:

(From RFC-3164):

4.1 syslog Message Parts

   The full format of a syslog message seen on the wire has three
   discernable parts.  The first part is called the PRI, the second part
   is the HEADER, and the third part is the MSG.  The total length of
   the packet MUST be 1024 bytes or less.  There is no minimum length of
   the syslog message although sending a syslog packet with no contents
   is worthless and SHOULD NOT be transmitted.

(From RFC-5424)

   The reason syslog transport receivers need only support receiving up
   to and including 480 octets has, among other things, to do with
   difficult delivery problems in a broken network.  Syslog messages may
   use a UDP transport mapping with this 480 octet restriction to avoid
   session overhead and message fragmentation.  In a network with
   problems, the likelihood of getting one single-packet message
   delivered successfully is higher than getting two message fragments
   delivered successfully.  Therefore, using a larger size may prevent
   the operator from getting some critical information about the
   problem, whereas using small messages might get that information to
   the operator.  It is recommended that messages intended for
   troubleshooting purposes should not be larger than 480 octets.  To
   further strengthen this point, it has also been observed that some
   UDP implementations generally do not support message sizes of more
   than 480 octets.  This behavior is very rare and may no longer be an
   issue.

...

   It must be noted that the IPv6 MTU is about 2.5 times 480.  An
   implementation targeted towards an IPv6-only environment might thus
   assume this as a larger minimum size.

With MTUs being what they are by default with ethernet, using an MTU <1500 with 
UDP when jumbo frames aren't available seems like a foolhardy thing to do.

I believe part of the problem is that the socket send buffer size is not being 
set in the SysLogHandler via socket.setsockopt and it's trying to jam as much 
information as it can down the pipe and failing, but I need to do more 
digging...

----------
nosy: +yaneurabeya

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