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Knowledge Base

Unable to install Plesk license: cURL cannot communicate with license server

 
dnsextensionsfirewallhost namehttp
  • License installation on a Plesk server fails:

    cURL cannot communicate with license server https://id-00.kaid.plesk.com:443/ (): Couldn't connect to server(7) cURL cannot communicate with license server https://id-00.kaid.plesk.com:443/ (): Couldn't resolve host name(6) (Error code: 2)

  • The hostname id-00.kaid.plesk.com is correctly resolved over DNS while checking with commands:

    • For Linux:

      # host id-00.kaid.plesk.com
      id-00.kaid.plesk.com is an alias for ka.plesk.com.
      ka.plesk.com has address 195.214.233.82
      ka.plesk.com has address 195.214.233.80
      ka.plesk.com has address 195.214.233.81

    • For Windows:

      C:> nslookup id-00.kaid.plesk.com
      Server:  UnKnown
      Address:  2620:0:28a9:4::1
      Non-authoritative answer:
      Name:    ka.plesk.com
      Addresses:  195.214.233.81
                195.214.233.80
                195.214.233.82
      Aliases:  id-00.kaid.plesk.com

  • The connection to licensing servers fails:

    # telnet ka.plesk.com 443
    Trying 195.214.233.82...
    telnet: Unable to connect to remote host: Connection refused

  • There are no blocking firewall rules for outbound traffic either in the local Firewall or in the external Firewall (if there is any)

  • Other operations on the server related to outgoing traffic, for example, packages installation or extensions catalog opening, fail as well:

    • For Linux

      # apt install nmap -y
      ..........
      Err:1 http://archive.ubuntu.com/ubuntu xenial InRelease
      Could not connect to archive.ubuntu.com:80 (203.0.113.2), - connection timed out [IP: 203.0.113.2 80]
      ..........

      # wget https://ext.plesk.com
      --2024-07-09 22:43:42-- https://ext.plesk.com/
      Resolving ext.plesk.com (ext.plesk.com)... 79.127.235.11, 79.127.235.9, 79.127.213.245, ...
      Connecting to ext.plesk.com (ext.plesk.com)|79.127.235.11|:443... connected.
      WARNING: Could not save SSL session data for socket 3
      Failed writing HTTP request: The specified session has been invalidated for some reason..
      Retrying.
      ..........

    • For Windows:

      C:> curl https://ext.plesk.com
      curl: (28) Failed to connect to ext.plesk.com port 443 after 21048 ms: Couldn't connect to server

Cause

Server-wide outgoing traffic issue. Most likely, issues on ISP/server provider side.

Resolution

Contact the ISP or server provider for further assistance.

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