Objective: How to set up an ACL or ACLs (Access Control Lists) on the ReadyNAS when an iSCSI LUN on ReadyNAS is accessed simultaneously by multiple iSCSI initiators (clients). Summary: It is recommended by the ReadyNAS team to setup an ACL or ACLs (Access Control Lists) on ReadyNAS frontview when an iSCSI LUN on the ReadyNAS is accessed simultaneously by more than one ISCSI initiators (clients). In the scenario, where there are 2 (or more than 2) iSCSI initiators (clients) are accessing the iSCSI LUN on ReadyNAS, the IQN (iSCSI Qualified Name) of each ISCSI initiator should be put in the ReadyNAS frontview Access Control List. The screenshots below outline how to check the IQN (iSCSI Qualified Name) from several different vendor’s iSCSI initiators and put it in ReadyNAS frontview. The steps below describe how to setup an ACL or ACL’S with: VMware Host and ReadyNAS Windows ISCSI initiator and ReadyNAS Linux ISCSI initiator and ReadyNAS Citrix Xen Server and ReadyNAS VMware Host and ReadyNAS Step 1: Check the IQN (iSCSI Qualified Name) of an iSCSI initiator in VMware Host. Using VI Client, connect to the VMware Host. Click on ‘Configuration’ tab on the top. From the left side menu, click on ‘Storage Adapters’. Under the ‘ISCSI software Adapter’, look for the IQN (iSCSI Qualified Name) as shown in the screenshot below. Step 2: Put the IQN of VMware Host in the ACL in ReadyNAS Frontview. On the ReadyNAS Frontview, Click on Volumes - > Volume Settings. Then click on the iSCSI tab. For each LUN, click on the ‘Modify’ button in front of it. Step 3: Select ‘Enabled’ from the drop down menu in front of ‘Access Control’. In the Initiator IQN(s) field, enter the IQN of the VMware host’s ISCSI software adaptor as recorded in Step 1. Then click on ‘ADD’. At this point, collect the IQN (iSCSI Qualified Name) from all the VMware hosts (and any other ISCSI initiator) accessing the ReadyNAS ISCSI target and add it here. Click on ‘Apply’ when finished. NOTE: Repeat the above step for all the LUNS in a target and for all the targets that are accessible by different iSCSI initiators simultaneously. Windows ISCSI initiator and ReadyNAS Step 1 Open the Microsoft software iSCSI initiator. Under the General tab of the iSCSI initiator window, IQN (iSCSI Qualified Name) is listed. Step 2 Put the IQN of Windows iSCSI initiator in the ACL in ReadyNAS frontview. On the ReadyNAS Frontview, Click on Volumes - > Volume Settings. Then click on the iSCSI tab. For each LUN, click on the ‘Modify’ button in front of it. Step 3 Select ‘Enabled’ from the drop down menu in front of ‘Access Control’. In the Initiator IQN(s) field, enter the IQN of the VMware host’s ISCSI software adaptor as recorded in Step 1. Then click on ‘ADD’. At this point, collect the IQN (iSCSI Qualified Name) from all the VMware hosts (and any other ISCSI initiator) accessing the ReadyNAS ISCSI LUN and add it here. Click on ‘Apply’ when finished NOTE: Repeat the above step for all the LUNS in a target and for all the targets that are accessible by different iSCSI initiators simultaneously. Linux ISCSI initiator and ReadyNAS. Step 1: The screenshot below is of the open source ISCSI initiator on Ubuntu Linux (version 8.x) . The IQN (iSCSI Qualified Name) of ISCSI initiator can be found in the file ‘initiatorname.iscsi’ under the path /etc/iscsi. Step 2 Put the IQN of Linux iSCSI initiator in the ACL in the ReadyNAS Frontview On the ReadyNAS Front view, Click on Volumes - > Volume Settings. Then click on the iSCSI tab. For each LUN, click on the ‘Modify’ button in front of it. Step 3 Select ‘Enabled’ from the drop down menu in front of ‘Access Control’. In the Initiator IQN(s) field, enter the IQN of Linux’s ISCSI software adaptor as recorded in Step 1. Then click ‘ADD’. At this point, collect the IQN (iSCSI Qualified Name) from all the Linux ISCSI initators (and any other ISCSI initiator) accessing the ReadyNAS iSCSI LUN and Add it. Click on ‘Apply’ when finished. NOTE: Repeat the above step for all the LUNS in a target and for all the targets that are accessible by different iSCSI initiators simultaneously. Citrix Xen Server and ReadyNAS Step 1 Connect to the Citrix XenServer using XenCenter. Under General Tab, the iSCSI IQN (iSCSI Qualified Name) is listed as outlined in the screenshot below. Step 2 Put the IQN of Citrix XenServer iSCSI initiator in the ACL in ReadyNAS frontview. On the ReadyNAS Front view, Click on Volumes - > Volume Settings. Then click on the iSCSI tab. For each LUN, click on the ‘Modify’ button in front of it. Step 3 Select ‘Enabled’ from the drop down menu in front of ‘Access Control’. In the Initiator IQN(s) field, enter the IQN of Citrix XenServer’s iSCSI initiator as recorded in Step 1. Then click on ‘ADD’. At this point, collect the IQN (iSCSI Qualified Name) from all the Linux ISCSI initators (and any other ISCSI initiator) accessing the ReadyNAS ISCSI target and Add it. Click on ‘Apply’ when finished. NOTE: Repeat the above step for all the LUNS in a target and for all the targets that are accessible by different iSCSI initiators simultaneously.