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Dell PowerConnect 5400 Switch config for EqualLogic iSCSI Network

At this current moment we use 2 PowerConnect 5424 switches for our iSCSI backend network.  The PowerConnect 5424 has 24 10/100/1000 BASE-T auto-sensing gigabit Ethernet switching ports and 4 SFP combo ports for fibre connectivity.

The PowerConnect series of switches have many good features some which are irrelevant to what I am talking about so I will leave this out and comment on the features which are important in relation to iSCSI backend networks. Notice I say backend, if this were not a backend network I may be interested in some of the other features such as multiple VLAN capability and iSCSI optimization and QOS. But as this is a backend network I will not require the use of multiple VLANS or iSCSI optimization as I don't see the need to optimise iSCSI on purely iSCSI network.

Firstly let’s take a look at some of the techcial bits;

the PowerConnect 5424 has a switch Fabric Capacity of 48.0 Gb/s , forwarding rate 35.6 Mpps and up to 8,000 Mac Address's in comparison the 5448 has a switch fabric capacity of 96.0 Gb/s forwarding rate of 71.2 Mpps and up to 8,000 MAC address's.

Link Aggregation Group (LAG) with support for up to 8 aggregated links per switch and up to 8 member ports per aggregated link (IEEE 802.3ad).  Jumbo frame support up to 10k. LACP (Link Aggregation Control Protocol) Support.

Once again High Availability being a must, the PowerConnect 5424 and 5428 series have the capability to connect to an external redundant power support with the use of PowerConnect RPS-600.

Web enabled management interface as well as a CLI accessible via Telnet, SSH or Serial port located on the back of the switch.  TFTP for transfer of config files and software.  Ability for dual software images.  Error and performance monitoring.

Switch access Password protection.  The ability to disable features such as Web,SSH,Telnet on a per-user basis and SSLv3 and SSHv2 encryption for switch management traffic.

Firstly check that your switch has an up to date software version.  Connect to yor switch using the RS232 cable supplied with the switch and use a VT100 compatible terminal emulation software such as Hyper Terminal, which is included with Windows XP but for some reason only known to Microsoft not with Windows 7 Professional, you can download a trial version of Hyper Terminal from Hilgrave.

Once downloaded create a new connection.  Select the Com port your cable is connected to, then select configure.

com port select

com port select


Port Settings.
Bits Per second (baud Rate) 9600 - the 5400 series of switch will support up to 38400 maximum baud, according to Dell PowerConnect Support. This is useful if you need to perform a software upgrade via your terminal application as increasing the bits per second increases the data transfer rate.
Data bits - 8
Parity - None
Stop bits - 1
Flow control- None

Port Settings

Port Settings


Once this is set, click ok. You will get a white screen with a flashing cursor, the terminal application is waiting for input, just press return and you will get you console prompt,  if the switch has already booted.

console prompt

console prompt


If you have not turned the switch on yet turn it on you will see the Power on Self-Test or POST screen.

post & image decompression

post & image decompression


After the POST tests have completed you can press ESC to enter the PROM Menu.

prom menu

prom menu


Here you can carry out diagnostics, set the baud rate of the switch and also download new software to the switch via you Terminal application.

Now for some basic configuration.

The most important configuration items that are iSCSI related include;

Enable Rapid Spanning Tree Protocol.
Enable spanning-tree portfast.
Enable Jumbo frames.
Disable storm control - remeber the iSCSI protocol is unicast and will flood the network by nature.
Enable flow control.

console> show version - Display Software Version, Boot Version and Hardware Version.

Delete the start-up configuration, this will give you a clean starting point.

console> enable
console# delete startup-config
Delete startup-config [y/n]?y

After deleting the start-up config reboot the switch.

console# reload
You haven't saved your changes. Are you sure you want to
continue ? (Y/N)[N]y
This command will reset the whole system and disconnect
your current session. Do you want to continue ? (Y/N)[N] y
Shutting down.....

When the switch reboots and goes through the POST tests, you will be greeted by the Dell Easy Setup Wizard, Answer no to the setup wizard.

Would you like to enter the setup wizard (you must answer this question within
60 seconds)? (Y/N)[Y] n

console>enable - Enter Privileged mode.
console# clock set 14:00:00 2 Jun 2011 - Obviously set your current time and date.
console# configure - Enter Configuration layer.
console(config)# user admin password ******** level 15 - Set a local username and password, used to login in to web interface.
console(config)# spanning-tree mode rstp - Set the Spanning tree mode to Rapid Spanning Tree.
console(config)# port jumbo-frame - Enable Jumbo Frames.
console(config)# interface range ethernet all - Configure all ports.
console(config-if)# spanning-tree portfast - Portfast causes the port to enter spanning-tree forwarding state immediately, bypassing the listening and learning state.
console(config-if)# speed 1000 - Set port Speed.
console(config-if)# duplex full - Set Full Duplex, flow control only works in full duplex mode.
console(config-if)# flowcontrol on - Enable flowcontrol.
console(config-if)# no port storm-control broadcast enable - Disable storm control.
console(config-if)# interface vlan 1 - Enter Configuration interface for vlan 1, this is the default vlan all ports by default are in this vlan.
console(config-if)# ip address /24 - Sets the ip address and subnetmask of for vlan 1.
console(config-if)# ip default-gateway - If you require a default gateway.
console(config-if)# exit - Exit config layer for vlan 1
console(config)# voice vlan oui-table remove 00036b - CISCO. Remove Vendor Specific voice vlan info.
console(config)# voice vlan oui-table remove 00096e - Avaya.
console(config)# voice vlan oui-table remove 0001e3 - Siemens.
console(config)# voice vlan oui-table remove 000fe2 - H3C.
console(config)# voice vlan oui-table remove 0060b9 - NEC/Philips.
console(config)# voice vlan oui-table remove 00d01e - Pingtel.
console(config)# voice vlan oui-table remove 00e075 - Polycom/Veritel.
console(config)# voice vlan oui-table remove 00e0bb - 3COM.
console(config)# no iscsi enable - Disable iSCSI priority.
console(config)# no iscsi target port 860 - Set no iSCSI target port.
console(config)# no iscsi target port 3260 - Set no iSCSI target port
console(config)# enable password level 15 ******** - Set enable password with level 15 access, after setting the enable password you will be prompted for it when entering enabled mode through CLI.
console(config)# line telnet - Enter Telnet config.
console(config-line)# password ******** - Set the Telnet password.
console(config-line)# exit

Copy the running config to the startup config and reboot the switch to apply the configuration at startup.

console# copy running-config startup-config
Overwrite file [startup-config] ?[Yes/press any key for no] y
....02-Jun-2011 16:31:10 %COPY-I-FILECPY: Files Copy - source URL running-config destination URL
02-Jun-2011 16:32:17 %COPY-N-TRAP: The copy operation
was completed successfully
Copy succeeded

Now reboot the switch.

console# reload
This command will reset the whole system and disconnect your current
session. Do you want to continue ? (Y/N)[N] y
Shutting down ...

Now you can access the web management interface using the switch ip address and the admin username and password we set, I would suggest doing a backup of the config just in case you need to revert back and update the firmware.

If you intend on using two switches for redundancy as outlined in my EqualLogic in a Hyper-V Environment post then I would seriously consider creating a LAG for Inter Switch traffic between the two switches, as these switches are not stackable.

console> enable
console# configure

console(config-if)# channel-group 1 mode auto
console(config-if)# int range port-channel 1
console(config-if)# no spanning-tree disable
console(config-if)# flowcontrol on
console(config-if)# exit
- Exit interface config layer.
console(config)# exit - Exit config layer.
console# copy running-config startup-config
Overwrite file [startup-config] ?[Yes/press any key for no] y

These steps should be repeated on the partner switch. Ports 21,22,23,24 are now members of a LAG or Link Aggregation Group with LACP enabled.

Note that when a port is in a LAG, its port specific configuration is ignored and the configuration of the LAG is applied to the member ports, and that a LAG is treated as a logical port, hence the use of interface command.
I have disabled spanning-tree on the LAG group, this is safe to do so as the 4 connections will be the only connections between the 2 switches, and there is no chance of creating a loop in such a simple setup.

I have bundled all the commands used into a .txt file downloadable below for ease of use, remember to delete the start-up config first.

5400config - Right click save target as.

    Comments (4) Trackbacks (0)
    1. Nice article, but I wonder that in your LAG group if you should also be configuring Jumbo frames (if of course they are used in your environment) as the LAG config is treated as a logical port hence the interface command?

      • Hi,
        I do currently have jumbo frames configured in our environment, I would always advise configuring jumbo frames in an iSCSI setup. Jumbo frames is configured globally for the device, this is done using the port jumbo-frame command ‘console(config)# port jumbo-frame’. As you can see from the command we are in the config layer and not the config-if layer suggesting that the command is global to the device and not interface specific. Jumbo frames will be enabled on the device including any LAG’s created.

    2. I noticed you were letting iSCSI traffic ride over the default VLAN. The documentation (as well as it being reiterated at the 2011 Dell Storage Forum) seems to be pretty clear that this shouldn’t be done (as I’ve seen some ugly side effects as well). Any particular reason why you’ve chosen this?

      I was in the middle of revamping my 5424’s, where most of the config mirror’s the typical Dell/EQL published docs. I was putting my iSCSI traffice on VLAN 100, then going to create a 4 port LAG for the interconnect. Mine looks slightly different than yours (in particular, you have the “interface range port-channel all” line in there, while I do not. Would you like to comment on my commands I was going to issue to create and configure the LAG:

      —-Create LAG Group—-
      interface range ethernet g3,g4,g5,g6
      channel-group 1 mode on
      interface port-channel 1
      flowcontrol on
      switchport mode trunk
      switchport trunk allowed vlan add 100
      copy running-config startup-config

      —-Enable PortFast on LAG Group—-
      spanning-tree mode rstp
      interface port-channel 1
      spanning-tree portfast
      copy running-config startup-config

      • Hi, and thanks for the comment. Some good info. When I configured the 5424 switches I did leave the ports in the default VLAN, at the time my understanding was that, as with any switch not using the default VLAN was related to security and not performance and as the 5424 switches were going to be isolated from the LAN that leaving them in the default VLAN was OK, (lazy I know). You are quite right I have heard that this may cause issues, when I spoke to EqualLogic tech support about it I didn’t really get a definitive answer as to what performance issues have been experienced, other than that “Things happen in the default VLAN that do not happen in other VLANS”, didn’t really cut the mustard with me! I personally have experienced no issues what so ever in leaving the 5424 in the default VLAN, but that doesn’t mean that no one else has.

        I would always suggest reading any technical documentation thoroughly, as you have done. I have recently done a post on configuring PowerConnect 5524 switches at which point I did create another VLAN and move all ports and LAGS into this VLAN.

        As for ‘interface range port-channel all’ this is a mistake, ignore.

        We purchased Dells, ‘Proactive Maintenence’ with our EqualLogic and after we had this carried out, the suggested amendments to our configuration where of course, move all ports out of the default VLAN, and that any LAG (ISL) or interconnect between non stacking switches should contain atleast 6 ports, ours at the time contain 4 ports.



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