search for: tcp_sack_permit

...es > 300 bytes. What ended up fixing the issue is tweaking the /dev/tcp module, and disabling selective acknowledgment (SACK). I ran the following command, and rsync worked fine with no special parameters between both hosts, using different transport mechanisms. -- bash-2.03# ndd -get /dev/tcp tcp_sack_permitted 2 bash-2.03# ndd -set /dev/tcp tcp_sack_permitted 0 bash-2.03# ndd -get /dev/tcp tcp_sack_permitted 0 -- After reading the man page (below) I set the parameter to 1, so that Solaris would accept connections using SACK, but not initiate connections using it. - This also worked for my two cases....