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ESX hosts disconnecting from VirtualCenter Server due to socket-related errors (1004300)


  • In VirtualCenter 2.0.2 and later releases, ESX hosts disconnect from the VirtualCenter Server due to socket-related errors.
  • When the VirtualCenter Server sends email alerts, the socket connections to the email server do not close, and the SMTP ports remain in the CLOSE_WAIT state for long periods of time.
  • The VirtualCenter log file contains multiple entries similar to:

    vpxd-0.log:[2007-10-31 15:19:44.414 'App' 5020 error] [VpxVmdbCnx] Authd error: Cannot connect to host An operation on a socket could not be performed because the system lacked sufficient buffer space or because a queue was full

    vpxd-0.log:[2007-10-31 15:43:43.036 'App' 628 verbose] [ScheduledTaskActionLRO] Failed to send email. Error:The message could not be sent to the SMTP server. The transport error code was 0x800ccc15. The server response was not available


After the VirtualCenter Server sends email alerts, the SMTP connections are terminated locally, and the socket connection to the email server closes. The ESX hosts remain connected to the VirtualCenter Server.

This issue is resolved in VirtualCenter 2.5 Update 1. Download the update here.

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