Syslog-ng duplicate log lines

Solution 1:

You're sending the log lines twice, because of these lines in rsyslogd.conf:

local7.info @log.remote.lan
local7.err @log.remote.lan

When you specify info, that means that info and all higher priorities will be sent, not only info. Since err has a higher priority than info, you can remove the second line, so the log will only be sent once.