Issue Could not update the license. Make sure that connections to the license server ka.plesk.com on TCP port 443 are not blocked

[abdallahoraby]

Server operating system version

CentOS 7.9.2009

Plesk version and microupdate number

Plesk Obsidian 18.0.59.2

Hi dears, itried to install the license using GUI but fails also i telnet this server but connection refused:
# telnet ka.plesk.com 443

telnet: connect to address 195.214.233.82: Connection refused

Any help please

 

[Kaspar@Plesk]

There are some suggestions in the support article you can try:

https://support.plesk.com/hc/en-us/articles/12388137260695--Plesk-license-fails-to-update-what-to-do

 

[abdallahoraby]

There are some suggestions in the support article you can try:

https://support.plesk.com/hc/en-us/articles/12388137260695--Plesk-license-fails-to-update-what-to-do

I tried all of these solutions:

- open these ports:
# iptables -I OUTPUT -p tcp -d 195.214.233.80,195.214.233.81,195.214.233.82 -m multiport --dports 443,5224 -j ACCEPT
# iptables -I INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT

- tried to install license via cmd:
# plesk bin license --install A00000-A00000-A00000-A00000-A00000
result:

 

[Kaspar@Plesk]

What the output of grep "ka.plesk.com" /etc/hosts and telnet 195.214.233.81 443?

 

[abdallahoraby]

What the output of grep "ka.plesk.com" /etc/hosts and telnet 195.214.233.81 443?

for this # grep "ka.plesk.com" /etc/hosts no output found
and for this # telnet 195.214.233.81 443
telnet: connect to address 195.214.233.81: Connection refused

 

[Kaspar@Plesk]

Looks like somehow any connection to the Plesk license servers gets blocked.

Are there any alternative firewall applications running (like firewalld for example)? If there are, stop and disable those and try a telnet ka.plesk.com 443 connection again.

Else you could try (if you haven't already), is to temporarily turn of the Plesk firewall and fail2ban. See if that makes any difference. If it doesn't, you can try to run iptables -F to Flush all iptables rules. This should normally not be necessary, but I might be worth a try. (Don't forget to turn your Firewall and Fail2ban back on once your finished.).

If that doesn't solve the issue either, there is likely some off-server firewall blocking the connection. In which is case it's probably best to ask your provider for assistance.