Overview
Introduction
48 POE+ ports. 4 SFP+ ports. L3 Managed enterprise grade switch! $120. Hell Yeah!
A few Server Builds members have purchased the Aruba S2500 switches from eBay and have had a ton of success with them. They show up in like new condition (mine had plastic wrap still installed) and work out of the box, with very little modification! They’re great ways to get 10GB into your house on the cheap and also replace expensive PoE switches.
For me this switch checked all the boxes. It’s got 48 ports. More than enough for most homelab needs. It’s got PoE/PoE+ to power your APs and IP Cameras. It’s got SFP+ to tickle my 10G fancy. This is the seller I bought from. I’ve got mine deployed now and I wanted to share some tips I mostly got from this youtube series. Check out his videos if you want to learn more 
Models
| Model | 1G Ethernet Ports | 10G SFP+ Ports | PoE | Power Supply | Price |
|---|---|---|---|---|---|
| S2500-24P | 24 | 4 | PoE, PoE+ | 580W | $97 |
| S2500-48P | 48 | 4 | Poe, PoE+ | 580W | $110 |
| S2500-24T | 24 | 4 | N/A | 150W | $79 |
| S2500-48T | 48 | 4 | N/A | 150W | $110 |
The Installation Guide from Aruba has a ton of good information in it!
Comparable switches
Nothing really comes close to the value of the S2500 especially if you’re looking for 10G and PoE in one package.
Cheapest SFP+ 10G: MicroTik CRS305-1G-4S+IN
- Price: Amazon: $138 / eBay: $141
- Ports: 1x1G, 4xSFP+ 10G
- PoE: No PoE output, but can be powered via PoE via the 1G port
Cheapest PoE & SFP: Netgear GS724TP
Cheap PoE 1G Switch: TP-Link 5/8 Port PoE
So even if you hobbled together some of the other switches you’d still come up short compared to the value you can get out of these Aruba units!
Unboxing
Here are a few pictures I snapped during my unboxing
Noise
The switch is much quieter than I expected. Even when the fans first spin up I’d consider it in the bearable range, but once they calm down after first boot it’s quiet for an enterprise grade 1u switch.
During Boot
On initial boot its decently loud, 57db according to my Apple Watch. Noise Sample During Boot.
While Running
After it finishes booting though it gets a lot quieter, 47db from that distance definitely within the realm of not annoying. Unless you’re sleeping next to this thing. Noise Sample During Normal Operation
Silencing Mod
The noise during normal use is completely unremarkable, but if it does bother you there is a guide for installing 40mm Noctua fans to make it completely silent.
Power Draw
I got out the Kill A Watt to do some power measurements for the 48 port PoE switch.
During Boot
When first powered on it drew about 55W from the wall with nothing plugged in.
At idle
After the boot process finished and things settled it ended up about 66W draw.
With APs
Once I plugged in the Unifi-AP-HD’s the draw went up a bit to 72W & 84W with one and two APs plugged in, respectively
This is confirmed by the Power Usage chart in the switch software.
Setup
The switch will probably work as an L2 switch right out of the box, but it is highly recommended that you at least factory reset it to ensure it doesn’t have any weird VLANs or ports settings messed with. In addition to the factory reset I’ll cover setting it up so you can access the web interface, updating to the latest firmware from HPE Aruba and enabling all 4 SFP+ ports for use.
Factory Reset
To factory reset the switch, use the buttons and screen on the front of the unit.
- Press the menu button until the cursor is on the “Maintenance” menu item
- Press the enter button to enter into the Maintenance menu and then keep pressing menu until you get to the “Factory Default” menu item and then press enter.
- When prompted to “Reload Box?” follow the onscreen directions and press enter to start the factory reset
- It takes about 3 minutes for the switch to factory reset.
At this point the switch is totally usable as an L2 Switch! Keep reading if you want to enable the web interface so you can mess with the L3 stuff, or if you want to enable all of the SFP+ ports for use.
Setting up Web Interface
After a factory reset you can set up the username and password for the web and SSH interfaces. To do this you need to navigate through the menus to the GUI Quick Setup and then plug a computer into the switch that you can use to set it up.
- Press the menu key on the switch until you find the “Maintenance” menu item.
- Press the enter button to enter the Maintenance menu and then keep pressing menu until you get to the “GUI Quick Setup” Menu item and press enter
- You’ll see a confirmation that “Quick-Setup invoked” this starts a 10 minute timer for you to proceed with the web interface setup
- Plug a computer into one of the front ports on the switch. Set the computer to DHCP and it should get a lease from the switch in the 172.16.0.0/24 subnet. (for me it was 172.16.0.253).
- You might have to open command prompt (“Start”->“Run”->type “cmd” and hit enter) and then run the commands “ipconfig /release” and then “ipconfig /renew” to get the DHCP lease from the switch
- Once you’ve got a DHCP lease you can open a browser (I used firefox, another youtuber recommends internet explorer in compatibility mode if you run into trouble) and navigate to http://172.168.0.254/ which should redirect you to https://172.168.0.254:4343/. If you get security warnings just click through the proceed option.
- In the web interface set the admin password (for use in the web interface and logging into SSH) and the Enable Mode password (for configuring more advanced features, which will be needed later to turn on the extra SFP+ ports. Set the date and time and leave Tunneled Server IP Address blank. Click Next.
- On the next screen you’ll set the IP Address of your switch. I use the 192.168.144.0/24 so I set the switch to 192.168.144.2 (my router is 192.168.144.1). You want to pick a static ip outside of the DHCP range of your router to avoid conflict. Set the subnetmask to 255.255.255.0 and the Default Gateway to the ip address of your router (for me, 192.168.144.1). You can leave the rest of the boxes as default and click next.
- Click Ok to the “No upstream ports are selected.” Dialog
- You’ll be presented with a summary of the changed you made, feel free to review them and then click Finish.
- The switch will start saving the configuration
- Once complete you should see a confirmation:
- Now you can plug your switch into the network with the rest of your devices as well as the PC you’re using to configure it. You might need to ipconfig /release & ipconfig /renew on your PC to get a normal DHCP lease again. Once you’ve got a normal DHCP lease, or have configured a static IP for your PC on the same subnet that you set the switch to you can access the web interface via http:// (for me http://192.168.144.2) and it will redirect you to the https login page.
- Use “admin” for the user and the password you previously set for admin
- We made it in!!!
Updating Firmware
Finding newer firmware
HPE bought Aruba in 2015 so there are two places you can get the firmware for this switch. The old Aruba site or from HP. I recommend getting it from the HP site since it is newer, but it requires login.
- Aruba Networks Firmware Page Older firmware, no login required
- HPE Networking Page Newer firmware, need to make a free account
Updating the firmware from the web interface
- Once you’ve downloaded the firmware you want to use navigate to your switch’s web interface at http:// and login using the credentials you made in the previous section.
- Click on the “Maintenance” section in the bottom left and you’ll be able to see the version that your switch currently has (for me 7.4.0.2)
- To update firmware, click on “Image Management” in the left nav
- Choose the local file option and browse to find the firmware you downloaded. Chose Yes to both “Reboot after upgrade” and “Save current before rebooting”.
- After you’ve got all the options set click “Upgrade Image”, you’ll see a progress bar.
- Once the firmware upgrade is complete you’ll see a dialog:
- Clicking okay will start a timer for the switch to reboot
- Let the switch reboot
- When I logged in I got security errors from https, just ignore those.
- After dismissing the security errors you are prompted to log in
- If you navigate to the “Maintenance” page again, you can see that you’re on the newer firmware now!
Enabling all 4 SFP+ Ports
Only two of the SFP+ ports are switching ports the other two are stacking ports for connecting mutliple Aruba switches together. If you want to use all 4 you need to SSH into the switch and disable the stacking interfaces.
When logged into the switch you can see the two yellow SFP+ ports, these are the stacking ports.
- Download putty if you don’t already have it and connect to the ip you set up for your switch previously
- Login with the username “admin” and the password you previously set for the admin user
- Type “en” and press enter to enter “Enable Mode” where you can do more advanced config. You’ll be prompted for the Enable Mode password you set up previously
- Type “show interface brief” and you can scroll through the interfaces with space bar until you see the stacking interfaces are listed here, we don’t want these…
- Type “delete stacking interface stack 1/2” and hit enter then type “delete stacking interface stack 1/3” and hit enter.
- Type “show interface brief” and press enter and then use space again to scroll through the interfaces and notice there are no longer any more stacking interfaces!
- If you refresh the web interface you should see the yellow stacking ports are now gone:
Success! You’ve now got 4 SFP+ interfaces! You are now ready to use your switch to it’s fullest capacities
Known Compatible Connectors
SFP Connectors are known to sometime be picky for certain manufacturers.
Officially Recommended SFP Connectors
Oficially Recommended DAC Cables
Official support list from Aruba Thanks @seanho!
Unofficial, but independently verified working Connectors
I’ll start updating with known compatible gear once people start testing this stuff in the wild
DAC Cables
To be determined
Transceivers
To be determined
Known not to work
To be determined
