Overcoming saturated ports in distributed data storage systems

A computer program product (CPP), comprising:

• a set of one or more computer-readable storage media;
• and
• program instructions, collectively stored in the set of one or more computer-readable storage media, for causing a processor set to perform the following computer operations:
• in response to detecting that ports of one or more host nodes are saturated, cause a standby node having standby ports to be activated;
• update a list of preferred communication paths to include communication paths that extend through the standby ports;
• send the updated list of preferred communication paths to a host;
• receive input/output (I/O) requests from the host along the communication paths that extend through the standby ports;
• in response to detecting that the saturated ports have been cleared, cause the standby node to be deactivated;
• receive I/O requests from the host along communication paths extending through the cleared ports of the host nodes;
• and
• in response to the standby node being deactivated, remove the communication paths that extend through the standby ports from the list of preferred communication paths.

A computer system (CS), comprising:

• a processor set;
• a set of one or more computer-readable storage media;
• program instructions, collectively stored in the set of one or more computer-readable storage media, for causing the processor set to perform the following computer operations:
• in response to detecting that ports of one or more host nodes are saturated, cause a standby node having standby ports to be activated;
• update a list of preferred communication paths to include communication paths that extend through the standby ports;
• send the updated list of preferred communication paths to a host;
• receive input/output (I/O) requests from the host along the communication paths that extend through the standby ports;
• in response to detecting that the saturated ports have been cleared, cause the standby node to be deactivated;
• receive I/O requests from the host along communication paths extending through the cleared ports of the host nodes;
• and
• in response to the standby node being deactivated, remove the communication paths that extend through the standby ports from the list of preferred communication paths.