I cannot connect to VPN using strongswan or ovpn on linux

my ipsec.conf

conn rmcnx6
keyexchange=ikev2
left=%any
leftid=<your_local_id>
leftauth=psk
right=197.159.66.165
rightauth=psk
ike=aes256-sha256-modp2048 # Phase 1 proposal
esp=aes256-sha256-modp2048 # Phase 2 proposal
dpdaction=restart
dpddelay=60s
dpdtimeout=90s
auto=start
rightsubnet=0.0.0.0/0
leftsourceip=%config

ipsec.secret
: PSK "<your_preshared_key>"


error i get

parsed IKE_SA_INIT response 0 [ N(NO_PROP) ] received NO_PROPOSAL_CHOSEN notify error establishing connection 'rmcnx6' failed

Hi @Omotola Adeb, what is your exact requirement? is it IPsec RA or SSLVPN RA? and what is the client you are using - Linux or Windows? and what is the remote access client you are using? Based on this, will get back with the suggestion.

I just want to have a successful access to the vpn via my openhead linux(access via SSH)

On windows with sophos connect it connects successfully. 
on Windows Openvpn not successful.
On linux, i used openVPN with the .ovpn file download from the user side, it was not successful.
I also used strongswan, not successfully.

I just want to have a successful access to the vpn via my openhead linux(access via SSH)

On windows with sophos connect it connects successfully. 
on Windows Openvpn not successful.
On linux, i used openVPN with the .ovpn file download from the user side, it was not successful.
I also used strongswan, not successfully.

* On Windows, use OpenVPN Connect (downloadable from Internet), after configuring the SSLVPN RA on SFOS, download the .ovpn file file from VPN portal (by the way you are on very very old SFOS with no support, recommended to upgrade to v20.0GA or latest MRs on v20) and use this file on OpenVPN Connect application.

* On Linux, whether it is UI based on CLI based, you can follow the same procedure mentioned above.

* On Linux, download Strongswan and build/install it, 

One example as below:

/etc/strongswan.conf

charon {
    reuse_ikesa = no
    threads = 32

    plugins {
        load-tester {
            # enable the plugin
            enable = yes
            initiators = 1
            iterations = 1
            delay = 250
            mode = tunnel
            version = 1
            initiator = <Linux ip>
            responder = <SFOS wan ip where ipsec ra configured> 
            responder_id = <SFOS wan ip>
            # IKE-proposal to use
            proposal = aes128-sha1-modp1024
            esp = aes256-sha2_256-modp1024
            initiator_auth = psk
            responder_auth = psk
            preshared_key = abcdef
            authby = psk
            # disable IKE_SA rekeying (default)
            ike_rekey = 0
            # enable CHILD_SA every 3200s
            initiator_tsr = <local subnet of Linux node>
            child_rekey = 3200
            # do not delete the IKE_SA after it has been established (default)
            delete_after_established = no
            # do not shut down the daemon if all IKE_SAs established
            shutdown_when_complete = no
        }
    }
}

Configure the above given IPsec phase1, phase2 proposals, psk on SFOS.

ipsec start // command on Linux node to initiate the tunnel.