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Backup jobs fail intermittently with Error observed by underlying BIO:


Intermittent network failures when communicating to the VMware host. The errors can vary but all have some variation of: 
“Error observed by underlying BIO: No such file or directoryDetail: 'SSL connect failed in tcp_connect()', endpoint:” 

Guest processing credentials test will also fail over VIX with this error, and you may get a pop up error bellow when editing the Vsphere host: 

User-added image

But on a second try it will continue.


Unsupported network configuration in VMware.  A vm kernel nic with Management is set on a port group no longer becomes eligible to have vms on it.  If a vmkernel port with management option is added to a network with vms attached you will see the following warning in VMware. 

User-added image

In Veeam we intermittently get the error “Error observed by underlying BIO: No such file or directoryDetail: 'SSL connect failed in tcp_connect()', endpoint:”,  however sometimes the jobs will work if retried enough times. 


Remove the Management vmkernel port from the vm network, or move the vms to a network without a management vmkernel port.
Veeam Backup & Replication
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