OpenVPN on OpenWRT: TLS Error: reading acknowledgement record from packet

I am trying to connect my (windows and apple) remote client to my home router so that I can remotely access servers and devices behind my firewall. I have installed all of the components on both the client and server, I think that my problem is in the configuration. I know that the certificate files are correct on both the client and server because this had been working at one point (I had to reset the router so the config and firewall files got wiped out).

Results from logread on the openvpn/openwrt router:

Sun May 19 16:20:07 2019 daemon.notice openvpn(my_server)[4784]: 185.245.86.12:55378 TLS: Initial packet from [AF_INET]185.245.86.12:55378, sid=0f4ceaba c69f7575 Sun May 19 16:20:07 2019 daemon.err openvpn(my_server)[4784]: 185.245.86.12:55378 TLS Error: reading acknowledgement record from packet Sun May 19 16:20:09 2019 daemon.err openvpn(my_server)[4784]: 185.245.86.12:55378 TLS Error: reading acknowledgement record from packet Sun May 19 16:20:13 2019 daemon.err openvpn(my_server)[4784]: 185.245.86.12:55378 TLS Error: reading acknowledgement record from packet Sun May 19 16:20:20 2019 daemon.err openvpn(my_server)[4784]: 185.245.86.12:55378 TLS Error: reading acknowledgement record from packet Sun May 19 16:20:37 2019 daemon.err openvpn(my_server)[4784]: 185.245.86.12:55378 TLS Error: reading acknowledgement record from packet Sun May 19 16:21:07 2019 daemon.err openvpn(my_server)[4784]: 185.245.86.12:55378 TLS Error: TLS key negotiation failed to occur within 60 seconds (check your network connectivity) Sun May 19 16:21:07 2019 daemon.err openvpn(my_server)[4784]: 185.245.86.12:55378 TLS Error: TLS handshake failed 

Here is my /etc/config/openvpn:

config openvpn 'my_server'         option enable '1'         option port '1194'         option proto 'udp'         option dev 'tap0'         option ca '/etc/openvpn/ca.crt'         option cert '/etc/openvpn/my-server.crt'         option key '/etc/openvpn/my-server.key'         option dh '/etc/openvpn/dh2048.pem'         option ifconfig_pool_persist '/tmp/ipp.txt'         option keepalive '10 120'         option 'comp_lzo' 'yes'         option persist_key '1'         option persist_tun '1'         option status '/tmp/openvpn-status.log'         option verb '3'         option server_bridge '192.168.1.1 255.255.255.0 192.168.1.200 192.168.1.219'         list push 'redirect-gateway def1'         list push 'dhcp-option DNS 192.168.1.1'         option enabled '1' 

Additional /etc/config/firewall settings:

config 'rule'         option 'target' 'ACCEPT'         option 'dest_port' '1194'         option 'src' 'wan'             option 'proto' 'tcpudp'         option 'family' 'ipv4' 

Additional /etc/config/dhcp settings:

    config dhcp 'lan'             option interface 'lan'             option ignore '0'             option start '50'             option limit '150' 

Client (Macbook) .opvn:

  client   dev tun   proto udp   fast-io   remote someplace-really-cool.com 1194   nobind   persist-key   persist-tun   verb 3   key-direction 1   cipher AES-128-CBC   auth SHA256  <ca> -----BEGIN CERTIFICATE----- ... -----END CERTIFICATE----- </ca> <cert> Certificate:     Data:         Version: 3 (0x2)         Serial Number: 4097 (0x1001)     Signature Algorithm: sha256WithRSAEncryption         Issuer: C=GB, ST=London, O=WWW Ltd.         Validity             Not Before: Jun 22 19:57:52 2018 GMT             Not After : Jun 19 19:57:52 2028 GMT         Subject: CN=my-client         Subject Public Key Info:             Public Key Algorithm: rsaEncryption                 Public-Key: (4096 bit)                 Modulus: ...                 Exponent: 65537 (0x10001)         X509v3 extensions:             X509v3 Key Usage:                  Digital Signature             X509v3 Extended Key Usage:                  TLS Web Client Authentication     Signature Algorithm: sha256WithRSAEncryption ... -----BEGIN CERTIFICATE----- ... -----END CERTIFICATE----- </cert> <key> -----BEGIN PRIVATE KEY----- ... -----END PRIVATE KEY----- </key> <tls-auth> # # 2048 bit OpenVPN static key # -----BEGIN OpenVPN Static key V1----- ... -----END OpenVPN Static key V1----- </tls-auth>   auth-nocache   client   dev tun   proto udp   fast-io   remote someplace-really-cool.com 1194   remote-cert-tls server   nobind   persist-key   persist-tun   verb 3   key-direction 1 <ca> -----BEGIN CERTIFICATE----- -----END CERTIFICATE----- </ca> <cert> Certificate:     Data:         Version: 3 (0x2)         Serial Number: 4097 (0x1001)     Signature Algorithm: sha256WithRSAEncryption         Issuer: C=GB, ST=London, O=WWW Ltd.         Validity             Not Before: Jun 22 19:57:52 2018 GMT             Not After : Jun 19 19:57:52 2028 GMT         Subject: CN=my-client         Subject Public Key Info:             Public Key Algorithm: rsaEncryption                 Public-Key: (4096 bit)                 Modulus: ... -----END CERTIFICATE----- </ca> <cert> Certificate:     Data:         Version: 3 (0x2)         Serial Number: 4097 (0x1001)     Signature Algorithm: sha256WithRSAEncryption         Issuer: C=GB, ST=London, O=WWW Ltd.         Validity             Not Before: Jun 22 19:57:52 2018 GMT             Not After : Jun 19 19:57:52 2028 GMT         Subject: CN=my-client         Subject Public Key Info:             Public Key Algorithm: rsaEncryption                 Public-Key: (4096 bit)                 Modulus: ...                 Exponent: 65537 (0x10001)         X509v3 extensions:             X509v3 Key Usage:                  Digital Signature             X509v3 Extended Key Usage:                  TLS Web Client Authentication     Signature Algorithm: sha256WithRSAEncryption ... -----BEGIN CERTIFICATE----- ... -----END CERTIFICATE----- </cert> <key> -----BEGIN PRIVATE KEY----- ... -----END PRIVATE KEY----- </key> <tls-auth> # # 2048 bit OpenVPN static key # -----BEGIN OpenVPN Static key V1----- ... -----END OpenVPN Static key V1----- </tls-auth> 

How to explain lack of 3 year Income Tax Return acknowledgement or Form 16A that is required?

I will be applying for a Schengen Visa in VFS Italy, and according to their website, we need to show Income Tax Return (ITR) acknowledgements or Form 16A of last 3 assessment years.

However, I only have Form 16A and ITR acknowledgement of 1 assessment year, as I was under the tax paying bracket before that, which means, I did not have to pay taxes, and therefore, didn’t get a Form 16 from my employers and didn’t file an ITR.

So, where and how can I explain this to the consulate? Will this be a problem?

Understanding acknowledgement mechanism in sliding window protocol

I came across following problem:

Node A sends packets to B through router R. The link A-R is instantaneous , but the R->B link transmits only 1 packet each second , one at a time . Assume A sends to B using sliding window protocol with window size =4 , For time t=2 , state what packets arrive at R and what are the packets present in the queue at R ?

The solution given was:

Since link A to B is instantaneous, at time 0, all frames 0,1,2,3,4… will be at router R. The window is of size 4. So, lets represent it as [0,1,2,3],4,…. Link R to B can transmit only 1 packet each second. So, at time 1, R will send frame 0 to B. At time 1, B will send ACK for packet 0 to R. So window at R will slide making it: 0,[1,2,3,4],…

The doubt

Go Back N uses cumulative acknowledgements, so what if at both time 0 and 1, router sends packet 0 and 1 to receiver? The router window at time 2, will still contain frames [0,1,2,3] as frame zero is not yet acknowledged. Is this wrong? Or I am wrong and sliding window protocol means Selective Repeat and it sends ACK for each frame?