Dell Configuration Guide for the S4048–ON System 9.14.2.4

Configuring iSCSI Optimization

To configure iSCSI optimization, use the following commands.

1. For a non-DCB environment: Enable session monitoring.
   CONFIGURATION mode
   cam-acl l2acl 4 ipv4acl 4 ipv6acl 0 ipv4qos 2 l2qos 1 l2pt 0 ipmacacl 0 vman-qos 0 ecfmacl 0 fcoeacl 0 iscsioptacl 2

   NOTE Content addressable memory (CAM) allocation is optional. If CAM is not allocated, the following features are disabled:

   • session monitoring
   • aging
   • class of service

   You can enable iSCSI even when allocated with zero (0) CAM blocks. However, if no CAM blocks are allocated, session monitoring is disabled and this information the show iscsi command displays this information.

2. For a non-DCB environment: Enable iSCSI.
   CONFIGURATION mode
   iscsi enable
3. For a DCB environment: Configure iSCSI Optimization.
   EXEC Privilege mode
   iSCSI configuration: copy CONFIG_TEMPLATE/iSCSI_DCB_Config running-config.
   The configuration files are stored in the flash memory in the CONFIG_TEMPLATE file.
   NOTE DCB/DCBx is enabled when you apply the iSCSI configuration in step 3. If you manually apply the iSCSI configuration by following steps 1 and 2, enable link layer discovery protocol (LLDP) before enabling iSCSI in step 2. You cannot disable LLDP if you enable iSCSI.
4. Save the configuration on the switch.
   EXEC Privilege mode
   write memory
5. Reload the switch.
   EXEC Privilege mode
   reload
   After the switch is reloaded, DCB/ DCBx and iSCSI monitoring are enabled.
6. (Optional) Configure the iSCSI target ports and optionally the IP addresses on which iSCSI communication is monitored.
   CONFIGURATION mode
   [no] iscsi target port tcp-port-1 [tcp-port-2...tcp-port-16] [ip-address address]
   • tcp-port-n is the TCP port number or a list of TCP port numbers on which the iSCSI target listens to requests. You can configure up to 16 target TCP ports on the switch in one command or multiple commands. The default is 860, 3260.

     Separate port numbers with a comma. If multiple IP addresses are mapped to a single TCP port, use the no iscsi target port tcp-port-n command to remove all IP addresses assigned to the TCP number.

     To delete a specific IP address from the TCP port, use the no iscsi target port tcp-port-n ip-address address command to specify the address to be deleted.

   • ip-address specifies the IP address of the iSCSI target. When you enter the no form of the command, and the TCP port you want to delete is one bound to a specific IP address, include the IP address value in the command.

     If multiple IP addresses are mapped to a single TCP port, use the no iscsi target port command to remove all IP addresses assigned to the TCP port number.

     To remove a single IP address from the TCP port, use the no iscsi target port ip-address command.

7. (Optional) Set the QoS policy that is applied to the iSCSI flows.
   CONFIGURATION mode
   [no] iscsi cos {enable | disable | dot1p vlan-priority-value [remark] | dscp dscp-value [remark]}
   • enable: enables the application of preferential QoS treatment to iSCSI traffic so that iSCSI packets are scheduled in the switch with a dot1p priority 4 regardless of the VLAN priority tag in the packet. The default is: iSCSI packets are handled with dotp1 priority 4 without remark.
   • disable: disables the application of preferential QoS treatment to iSCSI frames.
   • dot1p vlan-priority-value: specifies the virtual local area network (VLAN) priority tag assigned to incoming packets in an iSCSI session. The range is from 0 to 7. The default is: the dot1p value in ingress iSCSI frames is not changed and the same priority is used in iSCSI TLV advertisements if you do not enter the iscsi priority-bits command (Step 10).
   • dscp dscp-value: specifies the DSCP value assigned to incoming packets in an iSCSI session. The range is from 0 to 63. The default is: the DSCP value in ingress packets is not changed.
   • remark: marks incoming iSCSI packets with the configured dot1p or DSCP value when they egress the switch. The default is: the dot1 and DSCP values in egress packets are not changed.
8. (Optional) Set the aging time for iSCSI session monitoring.
   CONFIGURATION mode
   [no] iscsi aging time time.
   The range is from 5 to 43,200 minutes.
   The default is 10 minutes.
9. (Optional) Configures DCBX to send iSCSI TLV advertisements.
   LLDP CONFIGURATION mode or INTERFACE LLDP CONFIGURATION mode
   [no] advertise dcbx-app-tlv iscsi.
   You can send iSCSI TLVs either globally or on a specified interface. The interface configuration takes priority over global configuration.
   The default is Enabled.
10. (Optional) Configures the advertised priority bitmap in iSCSI application TLVs.
    LLDP CONFIGURATION mode
    [no] iscsi priority-bits.
    The default is 4 (0x10 in the bitmap).
11. (Optional) Configures the auto-detection of Compellent arrays on a port.
    INTERFACE mode
    [no] iscsi profile-compellent.
    The default is: Compellent disk arrays are not detected.