x300/docs: Clarified programming of IP addresses

2 files changed, 39 insertions, 58 deletions

diff --git a/host/docs/usrp_x3x0.rst b/host/docs/usrp_x3x0.rst
index 3b7e9914e..ee6960298 100644
--- a/host/docs/usrp_x3x0.rst
+++ b/host/docs/usrp_x3x0.rst
@@ -69,7 +69,7 @@ The next step is to make sure your computer can talk to the USRP. An otherwise u
 USRP device will have the IP address 192.168.10.2 when using 1GigE.
 It is recommended to directly connect your USRP to the computer at first,
 and to set the IP address on your machine to 192.168.10.1.
-See Section `Setup the host interface`_ on details how to change your machine's IP address.
+See the `system configuration manual <./usrp_x3x0_config.html>`_ on details how to change your machine's IP address.
 
 **Note**: If you are running an automatic IP configuration service such as Network Manager, make
 sure it is either deactivated or configured to not change the network device! This can, in extreme cases,
@@ -386,63 +386,21 @@ The default IP address for the USRP X300/X310 device depends on the Ethernet Por
 You must configure the host Ethernet interface with a static IP address on the same subnet as the connected 
 device to enable communication, as shown in the following table:
 
-+---------------+-------------------------+----------------+----------------+---------------+
-|  Ethernet     | USRP                    |  Default USRP  |  Host Static   | Host Static   |
-| Interface     | Ethernet Port           | IP Address     | IP Address     | Subnet Mask   |
-+===============+=========================+================+================+===============+
-|  Gigabit      |  Port 0 (HGS Image)     |  192.168.10.2  | 192.168.10.1   | 255.255.255.0 |
-+---------------+-------------------------+----------------+----------------+---------------+
-|  Ten Gigabit  |  Port 1 (HGS/XGS Image) |  192.168.40.2  | 192.168.40.1   | 255.255.255.0 |
-+---------------+-------------------------+----------------+----------------+---------------+
-|  Ten Gigabit  |  Port 0 (XGS Image)     |  192.168.30.2  | 192.168.30.1   | 255.255.255.0 |
-+---------------+-------------------------+----------------+----------------+---------------+
++---------------+-------------------------+----------------+----------------+---------------+---------------+
+|  Ethernet     | USRP                    |  Default USRP  |  Host Static   | Host Static   | Address       |
+| Interface     | Ethernet Port           | IP Address     | IP Address     | Subnet Mask   | EEPROM key    |
++===============+=========================+================+================+===============+===============+
+|  Gigabit      |  Port 0 (HGS Image)     |  192.168.10.2  | 192.168.10.1   | 255.255.255.0 | ``ip-addr0``  |
++---------------+-------------------------+----------------+----------------+---------------+---------------+
+|  Ten Gigabit  |  Port 0 (XGS Image)     |  192.168.30.2  | 192.168.30.1   | 255.255.255.0 | ``ip-addr2``  |
++---------------+-------------------------+----------------+----------------+---------------+---------------+
+|  Ten Gigabit  |  Port 1 (HGS/XGS Image) |  192.168.40.2  | 192.168.40.1   | 255.255.255.0 | ``ip-addr3``  |
++---------------+-------------------------+----------------+----------------+---------------+---------------+
 
+As you can see, the X300/X310 actually stores different IP addresses, which all address the device differently: Each combination of Ethernet port and interface type (i.e., Gigabit or Ten Gigabit) has its own IP address. As an example, when addressing the device through 1 Gigabit Ethernet on its first port (Port 0), the relevant IP address is the one stored in the EEPROM with key ``ip-addr0``, or 192.168.10.2 by default.
 
-On a Linux system, you can add a static IP address very easily by using the
-'ip' command
-
-::
-
-    sudo ip addr add 192.168.10.1/24 dev <interface>
-
-Note that **<interface>** is usually something like **eth0**.  You can discover the
-names of the network interfaces in your computer by running:
-
-::
-
-    ip addr show
-
-**Note:**
-When using UHD software, if an IP address for the USRP-X Series device is not specified,
-the software will use UDP broadcast packets to locate the USRP-X Series device.
-On some systems, the firewall will block UDP broadcast packets.
-It is recommended that you change or disable your firewall settings.
-
-On many Linux distributions, NetworkManager or similar tools may control the network interface.
-It is important to deactivate these tools for your device before continuing!
-
-^^^^^^^^^^^^^^^
-Setting the MTU
-^^^^^^^^^^^^^^^
-As UHD by default uses receive and transmit frames larger than the standard MTU of 1500 Bytes,
-the NIC needs to be configured to use a larger MTU when used with the USRP X series devices.
-
-::
-
-    sudo ip link set mtu 8192 dev <interface>
-
-Upon initialization UHD will probe for the maximum possible path MTU along the path between the USRP X series device
-and the host, both in receive and transmit direction.
-
-If the network hardware does not support MTUs as large as 8000 Bytes, passing the **send_frame_size** and **receive_frame_size**
-arguments will make UHD use smaller MTUs:
-
-::
-
-    uhd_usrp_probe --args='send_frame_size=<max send MTU>, recv_frame_size=<max receive MTU>'
-
-**Note:** This will most likely have a severe performance penalty.
-
+See the `system configuration manual <./usrp_x3x0_config.html>`_ on details
+how to change your machine's IP address and MTU size to work well with the X300.
 
 ^^^^^^^^^^^^^^^^^^^^^^^^^
 Multiple devices per host
@@ -477,6 +435,7 @@ You may need to change the USRP's IP address for several reasons:
 To change the USRP's IP address,
 you must know the current address of the USRP,
 and the network must be setup properly as described above.
+You must also know which IP address of the X300 you want to change, as identified by their address EEPROM key (e.g. ``ip-addr0``, see the table above).
 Run the following commands:
 
 **UNIX:**
@@ -484,14 +443,14 @@ Run the following commands:
 ::
 
     cd <install-path>/lib/uhd/utils
-    ./usrp_burn_mb_eeprom --args=<optional device args> --key=ip-addr --val=192.168.10.3
+    ./usrp_burn_mb_eeprom --args=<optional device args> --key=ip-addr0 --val=192.168.10.3
 
 **Windows:**
 
 ::
 
     cd <install-path>\lib\uhd\utils
-    usrp_burn_mb_eeprom.exe --args=<optional device args> --key=ip-addr --val=192.168.10.3
+    usrp_burn_mb_eeprom.exe --args=<optional device args> --key=ip-addr0 --val=192.168.10.3
 
 ---------------------
 Addressing the Device
diff --git a/host/docs/usrp_x3x0_config.rst b/host/docs/usrp_x3x0_config.rst
index 22ef8c595..4be247b04 100644
--- a/host/docs/usrp_x3x0_config.rst
+++ b/host/docs/usrp_x3x0_config.rst
@@ -46,6 +46,23 @@ You should open your NetworkManager configuration and tell it to ignore the
 network interface you are using. **This is not the same as simply setting
 a static IP address.** You *must* tell NetworkManager to ignore the interface.
 
+Changing the host's IP address
+-------------------------------------
+
+On a Linux system, you can add a static IP address very easily by using the
+'ip' command:
+
+::
+
+    sudo ip addr add 192.168.10.1/24 dev <interface>
+
+Note that **<interface>** is usually something like **eth0**.  You can discover the
+names of the network interfaces in your computer by running:
+
+::
+
+    ip addr show
+
 Configuring the Socket Buffers
 -------------------------------------
 It is necessary to increase the maximum size of the socket buffers to avoid
@@ -92,6 +109,11 @@ Firewall will often interfere with your ability to communicate with your USRP.
 You should configure your firewall to "trust" the interface you are using.
 Setting this properly depends on your OS and firewall configuration method.
 
+When using UHD software, if an IP address for the USRP-X Series device is not specified,
+the software will use UDP broadcast packets to locate the USRP-X Series device.
+On some systems, the firewall will block UDP broadcast packets.
+It is therefore recommended that you change or disable your firewall settings.
+
 Interface Configuration File (Fedora)
 -------------------------------------
 On Fedora systems, you can configure the network interface mostly from one