The runtime internal log should be initialized right after normal log
from configuration, prevent missing log from any actions that could be
happened between two initializations.
For partial init log data (does not end with a newline), the log writer
discard data after the last newline to make the log prettier, then write
the init end marker. This causes the marker could be written more than
once, since the second overflows will preserve the data which does
include the marker from the first write.
To fix this, ensure that the init end marker is only written once, and
the second overflows will preserve data until the marker instead of the
fixed initial size like the first one.
copy
fix get valid ifaces in nameservers_bsd
nameservers on MacOS can be found in resolv.conf reliably
nameservers on MacOS can be found in resolv.conf reliably
exclude local IPs from MacOS resolve conf check
use scutil for MacOS, simplify reinit logic to prevent duplicate calls
add more dns server fetching options
never skip OS resolver in IsDown check
split dsb and darwin nameserver methods, add delay for setting DNS on interface on network change.
increase delay to 5s but only on MacOS
Without verbose log, we use internal log writer with log level set to
debug. However, this will affect other writers, like console log, since
they are default to notice level.
By adopting FilteredLevelWriter, we can make internal log writer run in
debug level, but all others will run in default level instead.
