Here is the output from Mikrotik:
18:08:59 ovpn,info connection established from 5.x.x.x, port: 59506 to 5.15.44.255
18:08:59 ovpn,debug,packet sent P_CONTROL_HARD_RESET_SERVER_V2 kid=0 sid=8ba8aecee454dec4 pid=0 DATA len=0
18:08:59 ovpn,debug,packet rcvd P_CONTROL_HARD_RESET_CLIENT_V2 kid=0 sid=9ac07dc2ec111bdb pid=0 DATA len=0
18:08:59 ovpn,debug,packet sent P_ACK kid=0 sid=8ba8aecee454dec4 [0 sid=9ac07dc2ec111bdb] DATA len=0
18:08:59 ovpn,debug,packet rcvd P_CONTROL_HARD_RESET_CLIENT_V2 kid=0 sid=9ac07dc2ec111bdb [0 sid=8ba8aecee454dec4] pid=0 DATA len=0
18:08:59 ovpn,debug,packet sent P_ACK kid=0 sid=8ba8aecee454dec4 [0 sid=9ac07dc2ec111bdb] DATA len=0
18:08:59 ovpn,debug,packet rcvd P_CONTROL kid=0 sid=9ac07dc2ec111bdb pid=1 DATA len=281
18:08:59 ovpn,debug,packet sent P_ACK kid=0 sid=8ba8aecee454dec4 [1 sid=9ac07dc2ec111bdb] DATA len=0
18:08:59 ovpn,debug,packet sent P_CONTROL kid=0 sid=8ba8aecee454dec4 pid=1 DATA len=1400
18:08:59 ovpn,debug,packet sent P_CONTROL kid=0 sid=8ba8aecee454dec4 pid=2 DATA len=752
18:08:59 ovpn,debug,packet rcvd P_ACK kid=0 sid=9ac07dc2ec111bdb [1 sid=8ba8aecee454dec4] DATA len=0
18:08:59 ovpn,debug,packet rcvd P_CONTROL kid=0 sid=9ac07dc2ec111bdb [2 sid=8ba8aecee454dec4] pid=2 DATA len=1174
18:08:59 ovpn,debug,packet sent P_ACK kid=0 sid=8ba8aecee454dec4 [2 sid=9ac07dc2ec111bdb] DATA len=0
18:08:59 ovpn,debug,packet rcvd P_CONTROL kid=0 sid=9ac07dc2ec111bdb pid=3 DATA len=911
18:08:59 ovpn,debug,packet sent P_ACK kid=0 sid=8ba8aecee454dec4 [3 sid=9ac07dc2ec111bdb] DATA len=0
18:08:59 ovpn,debug,packet sent P_CONTROL kid=0 sid=8ba8aecee454dec4 pid=3 DATA len=51
18:08:59 ovpn,debug,packet rcvd P_CONTROL kid=0 sid=9ac07dc2ec111bdb [3 sid=8ba8aecee454dec4] pid=4 DATA len=469
18:08:59 ovpn,debug,packet sent P_ACK kid=0 sid=8ba8aecee454dec4 [4 sid=9ac07dc2ec111bdb] DATA len=0
18:08:59 ovpn,info 5.15.177.161: using encoding - AES-128-CBC/SHA512
18:08:59 ovpn,debug peer info: IV_VER=2.5.8 IV_PLAT=linux IV_PROTO=6 IV_NCP=2 IV_CIPHERS=AES-256-GCM:AES-128-GCM:AES-128-CBC IV_LZ4=1 IV_LZ4v2=1 IV_LZO=1 IV_COMP_STUB=1 IV_COMP_STUBv2=1 IV_TCPNL=1
18:08:59 ovpn,info,account openvpn_otthon2 logged in, 10.8.0.252 from 5.x.x.x
18:08:59 ovpn,debug,packet sent P_CONTROL kid=0 sid=8ba8aecee454dec4 pid=4 DATA len=229
18:08:59 ovpn,debug,packet rcvd P_ACK kid=0 sid=9ac07dc2ec111bdb [4 sid=8ba8aecee454dec4] DATA len=0
18:08:59 ovpn,info <ovpn-openvpn_otthon2>: connected
18:09:00 ovpn,debug,packet rcvd P_CONTROL kid=0 sid=9ac07dc2ec111bdb pid=5 DATA len=42
18:09:00 ovpn,debug,packet sent P_ACK kid=0 sid=8ba8aecee454dec4 [5 sid=9ac07dc2ec111bdb] DATA len=0
18:09:00 ovpn,debug,packet sent P_CONTROL kid=0 sid=8ba8aecee454dec4 pid=5 DATA len=131
18:09:00 ovpn,debug,packet rcvd P_ACK kid=0 sid=9ac07dc2ec111bdb [5 sid=8ba8aecee454dec4] DATA len=0
Here is the output from WRT based Openvpn client:
root@Otthon2:/etc/openvpn/config# /usr/sbin/openvpn --config /etc/openvpn/config/client.conf
2024-04-04 18:08:59 us=766256 DEPRECATED OPTION: --cipher set to 'AES-128-CBC' but missing in --data-ciphers (AES-256-GCM:AES-128-GCM). Future OpenVPN version will ignore --cipher for cipher negotiations. Add 'AES-128-CBC' to --data-ciphers or change --cipher 'AES-128-CBC' to --data-ciphers-fallback 'AES-128-CBC' to silence this warning.
2024-04-04 18:08:59 us=778417 OpenVPN 2.5.8 arm-openwrt-linux-gnu [SSL (OpenSSL)] [LZO] [LZ4] [EPOLL] [MH/PKTINFO] [AEAD]
2024-04-04 18:08:59 us=778649 library versions: OpenSSL 3.0.8 7 Feb 2023, LZO 2.10
2024-04-04 18:08:59 us=797719 WARNING: this configuration may cache passwords in memory – use the auth-nocache option to prevent this
2024-04-04 18:08:59 us=816906 Control Channel MTU parms [ L:1653 D:1212 EF:38 EB:0 ET:0 EL:3 ]
2024-04-04 18:08:59 us=944179 Data Channel MTU parms [ L:1653 D:1450 EF:121 EB:411 ET:32 EL:3 ]
2024-04-04 18:08:59 us=944552 Local Options String (VER=V4): 'V4,dev-type tap,link-mtu 1633,tun-mtu 1532,proto UDPv4,cipher AES-128-CBC,auth SHA512,keysize 128,key-method 2,tls-client'
2024-04-04 18:08:59 us=944672 Expected Remote Options String (VER=V4): 'V4,dev-type tap,link-mtu 1633,tun-mtu 1532,proto UDPv4,cipher AES-128-CBC,auth SHA512,keysize 128,key-method 2,tls-server'
2024-04-04 18:08:59 us=944885 TCP/UDP: Preserving recently used remote address: [AF_INET]5.x.x.x:1194
2024-04-04 18:08:59 us=945039 Socket Buffers: R=[180224->180224] S=[180224->180224]
2024-04-04 18:08:59 us=945152 UDP link local: (not bound)
2024-04-04 18:08:59 us=945266 UDP link remote: [AF_INET]5.x.x.x:1194
2024-04-04 18:08:59 us=945524 UDP WRITE [14] to [AF_INET]5.x.x.x:1194: P_CONTROL_HARD_RESET_CLIENT_V2 kid=0 [ ] pid=0 DATA len=0
2024-04-04 18:08:59 us=948992 UDP READ [14] from [AF_INET]5.x.x.x:1194: P_CONTROL_HARD_RESET_SERVER_V2 kid=0 [ ] pid=0 DATA len=0
2024-04-04 18:08:59 us=949175 TLS: Initial packet from [AF_INET]5.x.x.x:1194, sid=8ba8aece e454dec4
2024-04-04 18:08:59 us=949362 UDP WRITE [26] to [AF_INET]5.x.x.x:1194: P_CONTROL_HARD_RESET_CLIENT_V2 kid=0 [ 0 ] pid=0 DATA len=0
2024-04-04 18:08:59 us=949822 UDP READ [22] from [AF_INET]5.x.x.x:1194: P_ACK_V1 kid=0 [ 0 ]
2024-04-04 18:08:59 us=950365 UDP WRITE [295] to [AF_INET]5.x.x.x:1194: P_CONTROL_V1 kid=0 [ ] pid=1 DATA len=281
2024-04-04 18:08:59 us=950916 UDP READ [22] from [AF_INET]5.x.x.x:1194: P_ACK_V1 kid=0 [ 0 ]
2024-04-04 18:08:59 us=953076 UDP READ [22] from [AF_INET]5.x.x.x:1194: P_ACK_V1 kid=0 [ 1 ]
2024-04-04 18:09:00 us=48019 UDP READ [1414] from [AF_INET]5.x.x.x:1194: P_CONTROL_V1 kid=0 [ ] pid=1 DATA len=1400
2024-04-04 18:09:00 us=48511 UDP WRITE [22] to [AF_INET]5.x.x.x:1194: P_ACK_V1 kid=0 [ 1 ]
2024-04-04 18:09:00 us=48821 UDP READ [766] from [AF_INET]5.x.x.x:1194: P_CONTROL_V1 kid=0 [ ] pid=2 DATA len=752
2024-04-04 18:09:00 us=54528 VERIFY OK: depth=1, CN=barney.ro
2024-04-04 18:09:00 us=55874 VERIFY KU OK
2024-04-04 18:09:00 us=56027 Validating certificate extended key usage
2024-04-04 18:09:00 us=56139 ++ Certificate has EKU (str) TLS Web Server Authentication, expects TLS Web Server Authentication
2024-04-04 18:09:00 us=56246 VERIFY EKU OK
2024-04-04 18:09:00 us=56342 VERIFY OK: depth=0, CN=server.xxxxxxxx
2024-04-04 18:09:00 us=71660 UDP WRITE [1200] to [AF_INET]5.x.x.x:1194: P_CONTROL_V1 kid=0 [ 2 ] pid=2 DATA len=1174
2024-04-04 18:09:00 us=72160 UDP WRITE [925] to [AF_INET]5.x.x.x:1194: P_CONTROL_V1 kid=0 [ ] pid=3 DATA len=911
2024-04-04 18:09:00 us=74940 UDP READ [22] from [AF_INET]5.x.x.x:1194: P_ACK_V1 kid=0 [ 2 ]
2024-04-04 18:09:00 us=75896 UDP READ [22] from [AF_INET]5.x.x.x:1194: P_ACK_V1 kid=0 [ 3 ]
2024-04-04 18:09:00 us=82944 UDP READ [65] from [AF_INET]5.x.x.x:1194: P_CONTROL_V1 kid=0 [ ] pid=3 DATA len=51
2024-04-04 18:09:00 us=83778 UDP WRITE [495] to [AF_INET]5.x.x.x:1194: P_CONTROL_V1 kid=0 [ 3 ] pid=4 DATA len=469
2024-04-04 18:09:00 us=85899 UDP READ [22] from [AF_INET]5.x.x.x:1194: P_ACK_V1 kid=0 [ 4 ]
2024-04-04 18:09:00 us=90974 UDP READ [243] from [AF_INET]5.x.x.x:1194: P_CONTROL_V1 kid=0 [ ] pid=4 DATA len=229
2024-04-04 18:09:00 us=91612 UDP WRITE [22] to [AF_INET]5.x.x.x:1194: P_ACK_V1 kid=0 [ 4 ]
2024-04-04 18:09:00 us=91842 Control Channel: TLSv1.2, cipher TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, peer certificate: 2048 bit RSA, signature: RSA-SHA256
2024-04-04 18:09:00 us=92012 [server.xxxxxxx] Peer Connection Initiated with [AF_INET]5.x.x.x:1194
2024-04-04 18:09:00 us=95883 UDP READ [148] from [AF_INET]5.x.x.x:1194: P_DATA_V2 kid=0 DATA len=147
2024-04-04 18:09:00 us=96023 Key [AF_INET]5.x.x.x:1194 [0] not initialized (yet), dropping packet.
2024-04-04 18:09:00 us=119810 UDP READ [212] from [AF_INET]5.x.x.x:1194: P_DATA_V2 kid=0 DATA len=211
2024-04-04 18:09:00 us=119958 Key [AF_INET]5.x.x.x:1194 [0] not initialized (yet), dropping packet.
2024-04-04 18:09:01 us=187036 SENT CONTROL [server.xxxxxxx]: 'PUSH_REQUEST' (status=1)
2024-04-04 18:09:01 us=187525 UDP WRITE [56] to [AF_INET]5.x.x.x:1194: P_CONTROL_V1 kid=0 [ ] pid=5 DATA len=42
2024-04-04 18:09:01 us=189954 UDP READ [22] from [AF_INET]5.x.x.x:1194: P_ACK_V1 kid=0 [ 5 ]
2024-04-04 18:09:01 us=190421 UDP READ [145] from [AF_INET]5.x.x.x:1194: P_CONTROL_V1 kid=0 [ ] pid=5 DATA len=131
2024-04-04 18:09:01 us=190881 PUSH: Received control message: 'PUSH_REPLY,ping 20,ping-restart 60,route-gateway 10.8.0.1,ifconfig 10.8.0.252 255.255.255.0,peer-id 8'
2024-04-04 18:09:01 us=191329 OPTIONS IMPORT: timers and/or timeouts modified
2024-04-04 18:09:01 us=191511 OPTIONS IMPORT: --ifconfig/up options modified
2024-04-04 18:09:01 us=191682 OPTIONS IMPORT: route-related options modified
2024-04-04 18:09:01 us=191847 OPTIONS IMPORT: peer-id set
2024-04-04 18:09:01 us=192001 OPTIONS IMPORT: adjusting link_mtu to 1656
2024-04-04 18:09:01 us=192184 Using peer cipher 'AES-128-CBC'
2024-04-04 18:09:01 us=193638 Outgoing Data Channel: Cipher 'AES-128-CBC' initialized with 128 bit key
2024-04-04 18:09:01 us=193958 Outgoing Data Channel: Using 512 bit message hash 'SHA512' for HMAC authentication
2024-04-04 18:09:01 us=194196 Incoming Data Channel: Cipher 'AES-128-CBC' initialized with 128 bit key
2024-04-04 18:09:01 us=194465 Incoming Data Channel: Using 512 bit message hash 'SHA512' for HMAC authentication
2024-04-04 18:09:01 us=196923 TUN/TAP device tap11 opened
2024-04-04 18:09:01 us=197160 do_ifconfig, ipv4=1, ipv6=0
2024-04-04 18:09:01 us=197407 net_iface_mtu_set: mtu 1500 for tap11
2024-04-04 18:09:01 us=197737 sitnl_send: checking for received messages
2024-04-04 18:09:01 us=197945 sitnl_send: rtnl: received 36 bytes
2024-04-04 18:09:01 us=198214 net_iface_up: set tap11 up
2024-04-04 18:09:01 us=198496 sitnl_send: checking for received messages
2024-04-04 18:09:01 us=198689 sitnl_send: rtnl: received 36 bytes
2024-04-04 18:09:01 us=198903 net_addr_v4_add: 10.8.0.252/24 dev tap11
2024-04-04 18:09:01 us=199660 sitnl_send: checking for received messages
2024-04-04 18:09:01 us=199882 sitnl_send: rtnl: received 36 bytes
2024-04-04 18:09:01 us=200245 Initialization Sequence Completed
2024-04-04 18:09:01 us=200511 UDP WRITE [22] to [AF_INET]5.x.x.x:1194: P_ACK_V1 kid=0 [ 5 ]
2024-04-04 18:09:01 us=207227 UDP WRITE [132] to [AF_INET]5.x.x.x:1194: P_DATA_V2 kid=0 DATA len=131