goiscsi

A portable Go module for iscsi related operations such as discovery and login

Features

The following features are supported:

• Discover iSCSI targets provided by a specific portal, optionally log into each target
• Discover the iSCSI Initiators defined on the local system
• Log into a specific portal/target
• Log out of a specific portal/target
• Rescan all connected iSCSI sessions

Implementation options

Two implementations of the goiscsi.ISCSIinterface exist; one is for Linux based systems and one is a mock implementation. When instantiating an implementation of the goiscsi.ISCSIinterface interface, the factories accept a map[string]string option that allows the user to set specific key/values within the implementation.

The goiscsi.ISCSIinterface is defined as:

type ISCSIinterface interface {
	// Discover the targets exposed via a given portal
	// returns an array of ISCSITarget instances
	DiscoverTargets(address string, login bool) ([]ISCSITarget, error)

	// Get a list of iSCSI initiators defined in a specified file
	// To use the system default file of "/etc/iscsi/initiatorname.iscsi", provide a filename of ""
	GetInitiators(filename string) ([]string, error)

	// Log into a specified target
	PerformLogin(target ISCSITarget) error

	// Log out of a specified target
	PerformLogout(target ISCSITarget) error

	// Rescan current iSCSI sessions
	PerformRescan() error

	// generic implementations
	isMock() bool
	getOptions() map[string]string
}

Many operations deal with iSCSI Targets via a type of goiscsi.ISCSITarget, defined as:

type ISCSITarget struct {
	Portal   string
	GroupTag string
	Target   string
}

LinuxISCSI

When instantiating a Linux implementation via goiscsi.NewLinuxISCSI the following options are available

Key	Meaning
chrootDirectory	Run iscsiadm in a chrooted environment with the root set to this value.
	Default is to not chroot

MockISCSI

When instantiating a mock implementation via goiscsi.NewMockISCSI, the follwoing options are available:

Key	Meaning
numberOfInitiators	Defines the number of initiators that will be returned via the GetInitiators method. Default is "1"
numberOfTargets	Defines the number of targets that will be returned via the DiscoverTargets method. Default is "1"

Usage examples

The following example will instantiate a Linux based iSCSI client and Discover the targets exposed via the portal at address

import (
    "errors"
    
    "github.com/dell/goiscsi"
)

func printTargets(address string) {
    var c goiscsi.ISCSIinterface
    c := goiscsi.NewLinuxISCSI(map[string]string{})
    targets, err := c.DiscoverTargets(address, false)
    if err != nil {
        return
    }
    for _, t := range targets {
        fmt.Printf("Found target: %s", tgt.Target)
    }
}

The following example will instantiate a Mock iSCSI client, set the number of targets to 3, and Discover the mocked targets

import (
    "errors"
    
    "github.com/dell/goiscsi"
)

func printTargets(address string) {
    var c goiscsi.ISCSIinterface
    opts := make(map[string]string, 0)
    opts[goiscsi.MockNumberOfTargets] = "3"
    c := goiscsi.NewMockISCSI(opts)
    targets, err := c.DiscoverTargets(address, false)
    if err != nil {
        return
    }
    for _, t := range targets {
        fmt.Printf("Found target: %s", tgt.Target)
    }
}