Choices are ipv4, ipv6, or ipv4+ipv6.

Defaults to ipv4+ipv6.

Note: This parameter is identical to that provided by nvme-cli.

Default: Depends on kernel and other run time factors (e.g. number of CPUs).

Note: This parameter is identical to that provided by nvme-cli.

Default: Depends on kernel and other run time factors (e.g. number of CPUs).

Note: This parameter is identical to that provided by nvme-cli.

Default: Depends on kernel and other run time factors (e.g. number of CPUs).

Overrides the default number of elements in the I/O queues created by the driver. This option will be ignored for discovery, but will be passed on to the subsequent connect call.

Note: This parameter is identical to that provided by nvme-cli.

Defaults to 128.

Overrides the default delay before reconnect is attempted after a connect loss.

Note: This parameter is identical to that provided by nvme-cli.

Defaults to 10. Retry to connect every 10 seconds.

Overrides the default controller loss timeout period (in seconds).

Note: This parameter is identical to that provided by nvme-cli.

Defaults to 600 seconds (10 minutes).

Note: This parameter is identical to that provided by nvme-cli.

Defaults to false.

There is no guarantee that there will be a route to reach that IOC. However, we can use the socket option SO_BINDTODEVICE to force the connection to be made on a specific interface instead of letting the routing tables decide where to make the connection.

This option determines whether stacd will use SO_BINDTODEVICE to force connections on an interface or just rely on the routing tables. The default is to use SO_BINDTODEVICE, in other words, stacd does not ignore the interface.

BACKGROUND: By default, stacd will connect to IOCs on the same interface that was used to retrieve the discovery log pages. If stafd discovers a DC on an interface using mDNS, and stafd connects to that DC and retrieves the log pages, it is expected that the storage subsystems listed in the log pages are reachable on the same interface where the DC was discovered.

For example, let's say a DC is discovered on interface ens102. Then all the subsystems listed in the log pages retrieved from that DC must be reachable on interface ens102. If this doesn't work, for example you cannot "ping -I ens102 [storage-ip]", then the most likely explanation is that proxy arp is not enabled on the switch that the host is connected to on interface ens102. Whatever you do, resist the temptation to manually set up the routing tables or to add alternate routes going over a different interface than the one where the DC is located. That simply won't work. Make sure proxy arp is enabled on the switch first.

Setting routes won't work because, by default, stacd uses the SO_BINDTODEVICE socket option when it connects to IOCs. This option is used to force a socket connection to be made on a specific interface instead of letting the routing tables decide where to connect the socket. Even if you were to manually configure an alternate route on a different interface, the connections (i.e. host to IOC) will still be made on the interface where the DC was discovered by stafd.

Defaults to false.

In theory, hosts should only connect to IOCs that have been zoned for them. Connections to IOCs that a host is not zoned to have access to should simply not exist. In practice, however, users may not want hosts to disconnect from all IOCs in reaction to connectivity configuration changes (or at least for some of the IOC connections).

Some users may prefer for IOC connections to be "sticky" and only be removed manually (nvme-cli or exclude=) or removed by a system reboot. Specifically, they don't want IOC connections to be removed unexpectedly on DLPE removal. These users may want to set disconnect-scope to no-disconnect.

It is important to note that when IOC connections are removed, ongoing I/O transactions will be terminated immediately. There is no way to tell what happens to the data being exchanged when such an abrupt termination happens. If a host was in the middle of writing to a storage subsystem, there is a chance that outstanding I/O operations may not successfully complete.

Values:

Can take the values tcp, rdma, fc, or a combination thereof by separating them with a plus (+) sign. For example: tcp+fc. No spaces are allowed between values and the plus (+) sign.

Values:

If a host is currently failing to connect to an I/O controller and if the NCC bit associated with that I/O controller is asserted, the host can decide to stop trying to connect to that subsystem until connectivity is restored. This will be indicated by the CDC when it clears the NCC bit.

The parameter connect-attempts-on-ncc= controls whether stacd will take the NCC bit into account when attempting to connect to an I/O Controller. Setting connect-attempts-on-ncc= to 0 means that stacd will ignore the NCC bit and will keep trying to connect. Setting connect-attempts-on-ncc= to a non-zero value indicates the number of connection attempts that will be made before stacd gives up trying. Note that this value should be set to a value greater than 1. In fact, when set to 1, stacd will automatically use 2 instead. The reason for this is simple. It is possible that a first connect attempt may fail.

Defaults to 0.

controller=transport=[trtype];traddr=[traddr];trsvcid=[trsvcid];host-traddr=[traddr],host-iface=[iface];nqn=[nqn]


                

Fields

controller = transport=tcp;traddr=localhost;trsvcid=8009
controller = transport=tcp;traddr=2001:db8::370:7334;host-iface=enp0s8
controller = transport=fc;traddr=nn-0x204600a098cbcac6:pn-0x204700a098cbcac6


                    

The syntax is the same as for "controller", except that only transport, traddr, trsvcid, nqn, and host-iface apply. Multiple exclude= keywords may appear in the config file to specify more than 1 excluded controller.

Note 1: A minimal match approach is used to eliminate unwanted controllers. That is, you do not need to specify all the parameters to identify a controller. Just specifying the host-iface, for example, can be used to exclude all controllers on an interface.

Note 2: exclude= takes precedence over controller. A controller specified by the controller keyword, can be eliminated by the exclude= keyword.

Examples:

exclude = transport=tcp;traddr=fe80::2c6e:dee7:857:26bb # Eliminate a specific address
exclude = host-iface=enp0s8                             # Eliminate everything on this interface