The client where I installed the switch reported that an XP workstation (a Dell OptiPlex 755 with a gigabit NIC) was extremely slow to log on immediately after a reboot. Like five minutes or more slow. Once the logon did finally complete, I saw that a logon script had failed to map network drives, although I could map them manually. The issue did not seem to happen on older workstations with 10/100 NICs.

I spent some time chasing event log messages (like Userenv event 1053, “the RPC server is unavailable”) to no avail. To make a long story short, the solution is to enable Fast Link mode on the PowerConnect switch for all ports except those connected to routers, switches, and hubs. Once enabled for this device, I could complete a logon within a few seconds, even right after a reboot.

In PowerConnect 2824 web interface, go to the Switch > Spanning Tree > Port Settings page, and click Show All in the upper right corner. That opens a new page with all ports and settings. Enable Fast Link on the ports connected to endpoints like workstations and IP phones:

The Dell switch support team came through once again, this time with a helpful explanation of what Fast Link is doing and when to enable it. I later learned that this is not a new problem. Here's a relevant Cisco article apparently written in 2000:

Using PortFast and Other Commands to Fix Workstation Startup Connectivity Delays

As for why it took 5+ minutes for a logon to complete (when spanning tree negotiation should only take 30-40 seconds with Fast Link disabled), my hunch is that with Fast Link disabled, the workstation has issues even before a user logs on. If the workstation thinks that the network is there and immediately starts attempting to connect to the server (for running computer Group Policy etc.), that connection will fail if the switch port is still checking the spanning tree (listening and learning phases). Once that initial server connection fails, other things will be slow as well (DNS, logon, etc.). Fast Link lets the workstation connect to the server almost immediately, so DNS, time sync, and GPO processing can happen as expected.

Web, Not Command Line

Fiction:  the Getting Started Guide says, “The initial device configuration is through the Serial port.” It goes on to explain an elaborate procedure for connecting to the switch via the COM port using a VT100 emulator and setting up the switch using a command-line wizard. I found it hard to believe that there was no way to set up the switch from a web browser, but I valiantly unwound the included COM cable and set to work.

Fact:  After jumping through all the COM connection hoops, I could never get the command-line wizard to start. When I put the switch into managed mode, I got a message telling me to continue setup through the EWS (Embedded Web Server), but not giving an IP address to connect to. When I typed “enable” to start CLI mode, it told me the parameter was invalid (although no parameter should be required). According to the support rep, the CLI is disabled until you log in via the web interface, so you don't really need a COM connection

It's Easy If You Know What to Do

Basically all you need to do is set a computer IP address to 192.168.2.100, Subnet 255.255.255.0, plug the computer into the switch, and browse to http://192.168.2.1. Log in as “admin” (not “Admin”) with no password, check the box to enable the connection, select the radio button to use the default password, and Apply Changes. The switch will reboot and you'll be able to connect to the full web interface. (Okay, here it was helpful to have the COM connection because I was able to see that the switch didn't reboot the first time, so I had to repeat the process.) Don't forget to set your computer back to its normal IP configuration when you are done.

DHCP Settings

While I may want to give the switch a fixed IP at some point, as a shortcut to get it back on my main subnet, in the web interface, I went to System > IP Addressing > IP Interface and set DHCP to Enable. While the support rep was screaming, “NO! Wait! Wait!” I must have brushed the Apply Changes button because before I knew it, I was disconnected from the switch.

Again, the COM connection came in handy. First, it told me the new IP address. Alas, I could not reach it via a web browser to save my life. So the support rep had me enter the following commands to manually set the IP address (assuming 192.168.10.99 is on my local subnet):

console> enable
console# config
console(config)# interface vlan 1
console(config-if)# ip address 192.168.10.99 255.255.255.0

After that, I was able to connect to the switch via http://192.168.10.99. When I went in to the System > IP Addressing > IP Interface screen again, I saw that it had retrieved an IP address from DHCP, but the Apply DHCP Address check box was not checked. Apparently it pulls the IP address when you enable DHCP, but it doesn't actually apply it right away until you check that box and Apply Changes. Once I checked the box and clicked on Apply Changes, it immediately redirected me to the new, DHCP-assigned IP address, which worked fine.

Firmware Update

Even though I bought this switch in late December, the firmware update from October was not included, so I wanted to apply it.

The firmware upgrade, Firmware.PowerConnect_28xx-v10034.zip, contains a file called Downloading_Software.pdf which one is encouraged to read by the readme. Unfortunately this document is also lacking. It talks only about TFTP and XMODEM downloads. I tried the XMODEM download from HyperTerminal, but when I realized that would take over an hour to complete (at 9600 baud), I canceled it. I was getting ready to fiddle with TFTP, which I don't use often. The support rep suggested using the free TFTP server from solarwinds, and I found I already had it on my management station.

But then I noticed in the switch's web GUI under System > File Management > File Download that it can also download from an HTTP address. I have easy access to a web server so I copied the firmware files to the web server and prepared to download them through the web GUI.

Sigh. When you change the web GUI to “Download via HTTP”, the Source File box adds a Browse button; the only way to get data into that box is to choose a file on your local computer. Sure enough, all you have to do is choose HTTP and load the file from your desktop. It displays a nice little progress dialog and finishes in just a few minutes. Why all the obfuscation about XMODEM and TFTP in the documentation, when you can just download from your desktop?

By the way, although no reboot is requested, the firmware upgrade isn't applied until you “reset” (reboot) the switch.

This switch promises a lot of bang for the buck. I'm just hoping the hardware quality is way ahead of the documentation quality

Update 2/8/2010:  see this blog article for information on how and when to enable Spanning Tree Fast Link.