[strongSwan] Routing problem on Linux

[Old Kid]

Hello all,
My Windows 10 computer can connect to my strongswan server, though it has 
some weird behavoirs, it works at least. I need to share the VPN adapter's 
with Wifi, reset Wifi to DHCP, connect Wifi and VPN. Only after that I get 
a PPP adapter with default gateway 0.0.0.0 . But on Linux there is no route 
at all,
I use NetworkManager + strongswan plugin, after it connects I have:
default via 192.168.0.1 dev wlp3s0 proto dhcp metric 600 
192.168.0.0/24 dev wlp3s0 proto dhcp scope link src 192.168.0.2 metric 304 
192.168.0.0/24 dev wlp3s0 proto kernel scope link src 192.168.0.2 metric 
600 
192.168.20.100 dev wlp3s0 proto kernel scope link src 192.168.20.100 metric 
50 
192.168.20.100 dev wlp3s0 proto kernel scope link src 192.168.20.100 metric 
600 
avatar at archlinux:~$ 

I don't understand what the first column 192.168.20.100 means. I think it's 
supposed to be a subnet. And I don't think I can add a default route with 
this manually. In addtion, the strongswan android client can't connect at 
all, it says "giving up after 3 retransmits, establishing IKE_SA failed, 
peer not responding". Is there something with this configuration?

conn ikev2-vpn
        auto=route
        compress=no
        type=tunnel
        keyexchange=ikev2
        ike=aes256-aes128-sha256-sha1-modp3072-modp2048-modp1024
        fragmentation=yes
        forceencaps=yes
        dpdaction=clear
        dpddelay=300s
        left=%any
        leftid=@ipsecserver.com
        leftcert=ipsecserver.pem
        leftsendcert=always
        leftsubnet=0.0.0.0/0
        right=%any
        rightid=%any
        rightauth=eap-mschapv2
        leftsourceip=192.168.20.1
        rightsourceip=192.168.20.100/24
        rightdns=8.8.8.8,8.8.4.4
        rightsendcert=never
        eap_identity=%identity