We have two Ubuntu-20.04 servers in aws, different VPC, both installed StrongSwan and have configuration as below (ipsec.conf):
# basic configuration
config setup
# Add connections here.
conn %default
ikelifetime=28800s
lifetime=3600s
#rekeymargin= You choose; must match other side
keyingtries=%forever
keyexchange=ikev2
authby=secret
mobike=no
conn remote-side
# private ip
left=10.0.0.7
# vpc cidr
leftsubnet=10.0.0.0/24
# elastic ip
leftid=xxx.xxx.xxx.xxx
# private ip
leftsourceip=10.0.0.7
# elastic ip
right=xxx.xxx.xxx.xxx
# vpc cidr
rightsubnet=172.31.0.0/16
auto=start
type=tunnel
ike=aes256-sha1-modp1024!
esp=aes256-sha1!
dpddelay=30s
dpdtimeout=120s
dpdaction=restart
Left & right are switch on server 2, other config are identical
Pre shared key (ipsec.secrets) as below:
Server-1-IP Server-2-IP : PSK "AAABBBCCCDDD"
Also the two IPs are switched on server 2
IP forwarding:
net.ipv4.ip_forward = 1
net.ipv6.conf.all.forwarding = 1
net.ipv4.conf.all.accept_redirects = 0
net.ipv4.conf.all.send_redirects = 0
After run "sudo ipsec restart" the tunnel seems to build successfully.
#sudo ipsec status
Security Associations (1 up, 0 connecting):
remote-side[1]: ESTABLISHED 6 minutes ago, 10.0.0.7[xxx.xxx.xxx.xxx]...xxx.xxx.xxx.xxx[xxx.xxx.xxx.xxx]
#sudo ipsec statusall
Status of IKE charon daemon (strongSwan 5.8.2, Linux 5.4.0-1028-aws, x86_64):
uptime: 7 minutes, since May 26 01:47:35 2021
malloc: sbrk 2580480, mmap 0, used 620272, free 1960208
worker threads: 11 of 16 idle, 5/0/0/0 working, job queue: 0/0/0/0, scheduled: 5
loaded plugins: charon aesni aes rc2 sha2 sha1 md5 mgf1 random nonce x509 revocation constraints pubkey pkcs1 pkcs7 pkcs8 pkcs12 pgp dnskey sshkey pem openssl fips-prf gmp agent xcbc hmac gcm drbg attr kernel-netlink resolve socket-default connmark stroke updown eap-mschapv2 xauth-generic counters
Listening IP addresses:
10.0.0.7
Connections:
remote-side: 10.0.0.7...xxx.xxx.xxx.xxx IKEv2, dpddelay=30s
remote-side: local: [xxx.xxx.xxx.xxx] uses pre-shared key authentication
remote-side: remote: [xxx.xxx.xxx.xxx] uses pre-shared key authentication
remote-side: child: 10.0.0.0/24 === 172.31.0.0/16 TUNNEL, dpdaction=restart
Security Associations (1 up, 0 connecting):
remote-side[1]: ESTABLISHED 7 minutes ago, 10.0.0.7[xxx.xxx.xxx.xxx]...xxx.xxx.xxx.xxx[xxx.xxx.xxx.xxx]
remote-side[1]: IKEv2 SPIs: d32eda951e3c567e_i* 6b2ae87360a4a4dc_r, pre-shared key reauthentication in 7 hours
remote-side[1]: IKE proposal: AES_CBC_256/HMAC_SHA1_96/PRF_HMAC_SHA1/MODP_1024
UFW is inactive, aws security group is set to accept all TCP & UDP from anywhere (I know it's unsafe).
Both instances disabled source/destination check
However from either server I could not ping the other server by private ip address.
Any help is appreciated.
