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This page documents the computers and networking equipment directly related to the radome. General documentation of W1XM's networking stuff (to the extent that it exists) is located in Athena.

This wiki is currently public, do not put credentials or other sensitive data here.

Computers

Current computers relevant to radome operations are listed below.

New servers and other public facing machines being added should ideally follow the same naming scheme (Starfleet Engineers) both for continuity and to avoid namespace conflicts with other MIT entities since we seem to have successfully found a theme no one else was using.

w1xm-radar-1.mitrs.org

This server is a Factor 202 (industrialized Raspberry Pi) located in the climate-controlled rack on the roof directly under the radome.

It does the actual CANbus communication (see Overview) with the radome motor drives and serves a custom WebSocket-based protocol for controlling the dish remotely.

The WebSocket server and its protocol are in this Github.

This server is only accessible from within RSnet.

scotty.mitrs.org / scotty.mit.edu

This server is a Dell Precision Rack 7910 located in a rack in 54-1912.

It is used to run computations and recordings of data from the software-defined radio(s) for the radome. It is owned by the MIT UHF Repeater Association W1XM. It is primarily used for radio astronomy observations in JLab using the srt-py interface for the dish and has relatively limited storage (6TB of SSD under the /data partition) and is only capable of recording about 20 MHz total bandwidths. It is connected directly to the RF Data 10GB network for recording from the SDR at the radome.

This server is accessible from RSnet, MITnet, and the public Internet.

laforge.mitrs.org / laforge.mit.edu

This server is a Gigabyte R183-Z93-AAV1-000 located in a rack in 54-1912.

It is also used to run computations and recordings of data from the software-defined radio(s) for the radome. It is owned by MIT Junior Lab (Physics Dept.) and is used by their students remotely. This machine is connected directly to the RF Data 10GB network for recording from the SDR at the radome.

It has 18 TB of fast storage for SDR data recordings mounted under /data. This array consists of four 10 TB spinning drives and can handle about 50 MHz continuous recording in digital rf format. It also has an Nvidia Tesla T4 GPU that can be used for full bandwidth realtime FFT processing.

This server is accessible from RSnet, MITnet, and the public Internet.

obrien.mitrs.org

This server is a Supermicro X8SIA located in a rack in 54-1912 with a 59 TB raid array for archival RF data storage. It is not directly connected to the RF data network and cannot directly record from the SDR, It does, however, have a 10 GB point to point link to laforge.mitrs.org. This link can be accessed via obrien-fast.mitrs.org/laforge-fast.mitrs.org depending on which end of it you are on.

w1xm-eme-1.mitrs.org

This desktop computer is a Dell Optiplex 7910 located in 54-2101. It is used for casual (non-compute-heavy) access to the radome SDR data and general desktop use in the shack.

It is dual homed between RSnet and the RF data network and has a 10GB fiber link for the latter. It also has an Nvidia GPU comarable to that in laforge, albeit this currently does not work with the installed OS.

This computer is only accessible from within RSnet.

RF Data Network

The RF-Data fiber networking for the SDR data is separate from RSnet and MITnet in order to avoid contention between SDR data streams and normal network traffic.

The RF_Data network uses a single 10 GB switch located in 54-2101 (m54-2101-sw2.mitrs.org) to enable UDP connections between the radio at the radome and multiple different client computers. This switch connects via single mode fiber only, except for the management port which is accessible from the normal RS network. Note that presently (2026) only one computer can be in communication with the SDR at a time and will prevent other machines from connecting.

Currently, two fiber pairs are routed between the Ettus X300 at the radome and the the 54-2101 switch (albeit only one link is presently configured). Multiple fibers connect from the 54-2101 switch to w1xm-eme-1, scotty, and laforge.

When connecting new devices to the RF-Data network it is important to remember that single mode fiber connections require crossovers. Normal patch cables are crossover by default, however, if two of them are the series (for example a jumper between m54-2101-sw2 and the adjacent fiber patch panel, and between the patch bay in 54-1911 and a connected server), One of them will need to be uncrossed to make the link work. We have standardized on the uncrosse cable being at the 54-2101 connection.

RSnet Network

Radome control operates over the normal 1GB RSnet network. This manifests at Mikrotik switches in all locations at W1XM, These switches are arranged in a star configuration and linked to the central node in 54-1911 by 10 GB fiber links. Notably, our currentl router does not have enough SFP ports to support this, so the fiber fanout is from the switch located in the top of the righthand rack above the servers.

networking.1776218731.txt.gz · Last modified: 2026/04/15 02:05 by dsheen

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