Linux – OpenSwan – IPSec VPN – tunnel established but can’t see a specific server there

I have to connect my server to a VPN tunnel thought Internet to see a local server that is on IP 192.168.20.100

Here are IPSec AND IKE settings from server (not mine , I do not own the VPN server)

Settings

Here is tunnel data:

• Public IP: 213.0.XXX.YYY
• The local server I want to see: 192.168.20.100
• Network: 192.168.20.0/24
• Pre-Shared Key: XXXXXXXXXX

I've installed openswan on my CentOS 7 server (which is the client here)

Here is IPSec config from my client

# /etc/ipsec.conf
version 2.0     # conforms to second version of ipsec.conf specification

config setup
    nat_traversal=yes
    virtual_private=%v4:192.168.20.0/24
    protostack=netkey
    interfaces=ens160
    oe=off
    klipsdebug=all
    plutodebug="all"

conn l2tp-psk
    authby=secret
    pfs=no
    auto=add
    rekey=yes

    ikev2=insist
    ike=aes256-sha2_256
    #esp=aes256-sha2_256
    phase2alg=aes256-sha2_256
    compress=no

    type=tunnel
    left=149.56.XXX.YYY
    leftnexthop=%defaultroute
    leftprotoport=17/1701

    right=213.0.XXX.YYY
    rightsourceip=192.168.20.100
    rightsubnet=192.168.20.0/24
    rightnexthop=%defaultroute
    rightprotoport=17/1701

My ipsec.secret:

# /etc/ipsec.secrets
%any 213.0.XXX.YYY : PSK "XXXXXXXXXXXXXXXXX"

When I execute "ipsec auto –up l2tp-psk" the tunnel is established correctly:

002 "l2tp-psk": terminating SAs using this connection
002 "l2tp-psk" #506: deleting state #506 (STATE_PARENT_I3)
005 "l2tp-psk" #506: ESP traffic information: in=0B out=0B
002 "l2tp-psk" #505: deleting state #505 (STATE_PARENT_I3)
002 "l2tp-psk": deleting connection
002 added connection description "l2tp-psk"
002 "l2tp-psk" #507: initiating v2 parent SA
133 "l2tp-psk" #507: STATE_PARENT_I1: initiate
133 "l2tp-psk" #507: STATE_PARENT_I1: sent v2I1, expected v2R1
133 "l2tp-psk" #507: STATE_PARENT_I1: sent v2I1, expected v2R1
134 "l2tp-psk" #508: STATE_PARENT_I2: sent v2I2, expected v2R2 {auth=IKEv2 cipher=aes_256 integ=sha256_128 prf=OAKLEY_SHA2_256 group=MODP1536}
002 "l2tp-psk" #508: IKEv2 mode peer ID is ID_IPV4_ADDR: '213.0.XXX.YYY'
002 "l2tp-psk" #508: negotiated tunnel [149.56.XXX.YYY,149.56.XXX.YYY:1701-1701 17] -> [192.168.20.0,192.168.20.255:1701-1701 17]
004 "l2tp-psk" #508: STATE_PARENT_I3: PARENT SA established tunnel mode {ESP=>0x6856ad5c <0x15452663 xfrm=AES_256-HMAC_SHA2_256 NATOA=none NATD=none DPD=passive}

But when I ping 192.168.20.100 there is no response (ping on that server is allowed).

I don't own the VPN server network or local server on 192.168.20.100 but I can ask questions to the owners.

What should I try? I'm suposed to be able to see an Oracle service running on 192.168.20.100:1521

Thanks in advance.