1. How to Configure a Custom Management IP Address

1.1. Modifying Management IP Address

This procedure is broken down into three distinct sections: Adding the new IP address, removing the old one, and then making the modifications persistent. This is a bad section in which to try and take short-cuts: if you make a mistake, you’ll need to either mount the SD card file system on another computer to try and fix your changes, or else use a new SD card.


Laboratory Use Only READ SECTION VERY CAREFULLY prior to changing device IP address. Failure to follow instructions may render your device unreachable, and may require you to manually edit the SD card file system or make a new SD card.

1.2. Add New Management IP address


This procedure will need to be done for each MGMT port on your device.

Make sure that you’ve already configured the host IP address. You can see how to do this here. This will ensure that once you update Crimson TNG or Cyan, you’ll be able to communicate with it.

To temporarily add a new IP address, SSH into Crimson TNG (shown) or Cyan, and then add the new IP address using the IP tool;

[dev0@crimson]$ sudo -i
{Type Password}
 ip addr add Y.Y.Y.Y/ZZ dev eth0

Then, log out of Crimson TNG or Cyan, and without powering down the unit, test to confirm that the new IP address works, and that your host can communicate. The best test series is to first attempt to ping the new management port, then to run uhd_find_devices, and uhd_usrp_probe, and then to run a simple GNU Radio script that is known to work - and ensuring that you have also applied your final, intended, configuration on the host computer as well. You can do this by using the how to test successful setup and operation guide.

1.3. Removing Management IP address


Laboratory Use Only CAREFULLY TEST CHANGES TO NETWORK PARAMETERS, AND ENSURE FUNCTIONALITY, PRIOR TO MAKING THESE CHANGES PERSISTENT ACROSS REBOOTS Consider whether it is feasible to only add the new interface settings to Crimson TNG or Cyan, without removing the existing interface. This provides a fall back mechanism to access the device in the event you misconfigure the interface, and helps avoid incorrectly configuring the device, thereby ensuring consistent operation.

To remove the default management IP address, first ADD the new one using the procedure above. Then, log out of Crimson (shown) or Cyan, and SSH back in, using the NEW ip address. This will prevent your session from being terminated once you delete the old address.

To delete the old address on Crimson TNG or Cyan, we can again use the IP address tool;

[dev0@crimson]$ sudo ip addr del W.W.W.W/XX dev eth0

Again, log out of the machine, and ensure that you can ping the device, that the website is reachable, and that you can use uhd_usrp_probe and uhd_find_devices.

If you are unable to reach the website, or run any scripts, then STOP here and FIX the problem. At this point, your Crimson TNG or Cyan device is effectively configured with the new address, but the change is not persistent. This means that if you have to debug problems, do so now.

1.4. Validating New IP addresses

It is a very wise idea to test the new changes prior to making them persistent. To do this, you will want to separately validate communication between host machine and the Crimson TNG or Cyan SDR.

To do this, first attempt to ping the new management port from the host machine. This verifies connectivity from the host machine to the Crimson device. Next, validate the connectivity from the SDR device to the host machine by SSH’ing into the SDR, using the new IP address, and attempting to ping the host machine IP that should be on the same subnet as the Crimson device.

1.5. Persistently Update Management IP address


Laboratory Use Only CAREFULLY TEST CHANGES TO NETWORK PARAMETERS, AND ENSURE FUNCTIONALITY, PRIOR TO MAKING THESE CHANGES PERSISTENT ACROSS REBOOTS Carefully test network settings, using the previously described procedures to temporarily set and remove IP address, prior to making those changes persistent. If you are not able to get the configuration working temporarily, then persistently applying these settings across reboots, shall prevent communication with Crimson TNG or Cyan.

To ensure that the new IP address is persistent across reboots, SSH into Crimson TNG or Cyan, and modify the file located at: /etc/network/interfaces

For a Cyan also edit /etc/init.d/networking to replace all instances of the default IP address with the new IP address.

Once you write to these files, the changes will be applied on the next reboot.

Make sure that you have tested ALL configuration settings PRIOR to writing them to this file. If you weren’t able to get your configuration working temporarily, using the previous two instructions, then making them persistent across reboots SHALL NOT work. Making a broken configuration persistent will only serve to render rebooting the device to undo your changes and fix any earlier mistakes impossible.

Now that you are connected to the network, you can set up the software you will need to interface with your radio.

2. Custom Data IP Addresses

The IP addresses for the SFP+ (for Crimson) and QSFP+ (for Cyan) data ports may be changed temporarily or persistently as described in How-to 15: Get and Set Paths in UHD and the State Tree.