Instead of checking current dnstap output file size and potentially
synchronously calling dns_dt_reopen() upon every call to dns_dt_send():
- call dns_dt_reopen() asynchronously by queuing an event to the task
specified at dnstap environment creation time,
- ensure no roll event is outstanding before checking dnstap output
file size and potentially queuing another roll event.
This causes dnstap output files to exceed their configured size limits,
but prevents any two threads from performing the roll simultaneously
(which causes crashes).
Instead of relying on the caller to set up task-exclusive mode, make
dns_dt_reopen() enforce task-exclusive mode itself, using the task
specified at dnstap environment creation time.
Implement a new variant of dns_dt_create() to enable a dnstap
environment structure to hold the task in the context of which
dns_dt_reopen() will be executed.
4579. [func] Logging channels and dnstap output files can now
be configured with a "suffix" option, set to
either "increment" or "timestamp", indicating
whether to use incrementing numbers or timestamps
as the file suffix when rolling over a log file.
[RT #42838]
4572. [func] The "dnstap-output" option can now take "size" and
"versions" parameters to indicate the maximum size
a dnstap log file can grow before rolling to a new
file, and how many old files to retain. [RT #44502]
4411. [func] "rndc dnstap -roll" automatically rolls the
dnstap output file; the previous version is
saved with ".0" suffix, and earlier versions
with ".1" and so on. An optional numeric argument
indicates how many prior files to save. [RT #42830]
4235. [func] Added support in named for "dnstap", a fast method of
capturing and logging DNS traffic, and a new command
"dnstap-read" to read a dnstap log file. Use
"configure --enable-dnstap" to enable this
feature (note that this requires libprotobuf-c
and libfstrm). See the ARM for configuration details.
Thanks to Robert Edmonds of Farsight Security.
[RT #40211]
