I recently configured a IPSEC site-to-site (L2L in cisco language) with a ClearOS router running OpenSwan against a Cisco ASA5505. The first thing I tried (and did not work) was to add Tim Burgess marketplace add-in “Static IPsec VPN Basic.” Using this add-in the basic configuration was created, but the phase 2 transports do not match the options that Cisco has. I edited the ipsec config in /etc/ipsec.d/ipsec.unmanaged.xxx.conf and added these lines,
pfs=no
ike=aes256-sha1
esp=3des-md5
auth=esp
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