Add documentation section with commands to query the cache

`nix-serve` does not handle duplicates in the path:
```
hut$ curl http://127.0.0.1:5000/nix-cache-info
StoreDir: /nix/store
WantMassQuery: 1
Priority: 30
hut$ curl http://127.0.0.1:5000//nix-cache-info
File not found.
```

This meant that the cache was not accessible via:
`curl https://jungle.bsc.es/cache/nix-cache-info` but
`curl https://jungle.bsc.es/cachenix-cache-info` worked.

doc/2025-05-maintenance-purchase.md

@@ -1,156 +0,0 @@
-# Maintenance purchase 2025-05
-
-We need to buy some components to replace broken parts or to have spare ones for
-when they break. We also need some tools to do basic repairs.
-
-Here is the list:
-
-- 11 x Power supply DELTA DPS-750XB A (700 W) (this is critical)
-  - 57.69€/unit, 634.59€ total <https://es.aliexpress.com/item/1005004090017186.html>
-
-- 8 x RAM DDR4 2400MHz PC4-19200 ECC Registered
-  - 128.85€/pair, 515.40€ total <https://www.amazon.es/PC4-19200-REGISTERED-MEMORY-WORKSTATIONS-MOTHERBOARDS/dp/B06W9P3RKF>
-
-- 1 x Set of screwdrivers
-  - 23.99€ <https://www.amazon.es/BLOSTM-Juego-Destornilladores-Profesionales-Destornillador/dp/B09W9R8J3S>
-
-- 1 x UART adaptor
-  - 14.99€ <https://www.amazon.es/DSD-TECH-SH-U09C5-convertidor-Soporte/dp/B07WX2DSVB>
-
-- 1 x SSD SATA disk of 2 TB
-  - 135.99€ <https://www.amazon.es/Crucial-BX500-pulgadas-interno-CT2000BX500SSD101/dp/B0CCN9QWKT>
-
-Total: 1324.96 €
-
-# Rationale
-
-Below is the search procedure I followed to come up with that list.
-
-## Power supplies
-
-They are the first components to fail. We already have some problems with the
-monitoring of some power supplies. They will soon stop being manufactured, so we
-should increase out stack.
-
-Most Xeon nodes use the DELTA DPS-750XB A:
-
-    hut% sudo ipmitool fru
-    ...
-    FRU Device Description : Pwr Supply 1 FRU (ID 2)
-     Product Manufacturer  : DELTA
-     Product Name          : DPS-750XB A
-     Product Part Number   : E98791-010
-     Product Version       : 05
-     Product Serial        : XXXXXXXXXXXXXXXXX
-
-And we only have one per node. We should make the power supply redundant so we
-can tolerate it to fail without bringing down the node.
-
-They are available on Amazon, but they are very expensive (287.54 €):
-
-<https://www.amazon.es/DPS-750XB-E98791-010-alimentaci%C3%B3n-conmutada-Platinum/dp/B0DB65G4VT>
-
-On Aliexpress they are much cheaper (57.69 €):
-
-<https://es.aliexpress.com/item/1005004090017186.html>
-
-We have 11 nodes plus the login, but I'm not able to figure out which power
-supply the login is using.
-
-The login uses another one, AXX1100PCRPS, and only has one slot populated. We
-may want to also we another one, but I would need to reset the FRU and I don't
-have access to the login node. So I will leave this for Operations to deal with.
-We can live without the login if needed.
-
-## RAM DIMM
-
-The DIMM modules also experience errors, which are monitored by Linux. In some
-nodes we see non-recoverable errors that are no longer corrected by the ECC. We
-need to replace the bad modules.
-
-Having two spare modules per node would be enough to cover most problems in the
-future.
-
-> 16 GB, 2400 MHz RDIMM
-
-The module from dmidecode:
-
-    Handle 0x0026, DMI type 17, 40 bytes
-    Memory Device
-        Array Handle: 0x0020
-        Error Information Handle: Not Provided
-        Total Width: 72 bits
-        Data Width: 64 bits
-        Size: 16 GB
-        Form Factor: DIMM
-        Set: None
-        Locator: DIMM_B1
-        Bank Locator: NODE 1
-        Type: DDR4
-        Type Detail: Synchronous
-        Speed: 2400 MT/s
-        Manufacturer: Micron
-        Serial Number: XXXXXXXX
-        Asset Tag:
-        Part Number: 36ASF2G72PZ-2G3B1
-        Rank: 2
-        Configured Memory Speed: 2400 MT/s
-        Minimum Voltage: Unknown
-        Maximum Voltage: Unknown
-        Configured Voltage: Unknown
-
-Which is this module:
-
-<https://www.amazon.com/Micron-PC4-19200-DDR4-2400MHz-Registered-MTA36ASF2G72PZ-2G3B1/dp/B01KBCNEGI>
-
-But they have only one in stock. Here is more details:
-
-> 16GB PC4-19200 DDR4-2400MHz 
-
-The must have the following features:
-
-- 16 GB
-- DDR4
-- Speed at least 2400 MT/s
-- ECC
-- Registered
-- Best if from Micron
-
-I would say having 8 spare modules would be enough for now, as we only have a
-few that are currently failing. We could upgrade the modules later, as they
-don't have much risk of stopping being manufactured like the power supplies.
-
-These may work:
-
-- 1 x 16GB, 69,11€ <https://www.amazon.es/PC4-19200-REGISTRADO-SERVIDORES-Estaciones-CHIPKILL/dp/B06X42HC9N>
-
-- 2 x 16GB, 128,85€ <https://www.amazon.es/PC4-19200-REGISTERED-MEMORY-WORKSTATIONS-MOTHERBOARDS/dp/B06W9P3RKF>
-
-It is cheaper to buy them by pairs, so let's use the last one.
-
-## Screwdriver set
-
-In order to change and replace the machine parts we need a set of screwdrivers.
-Instead of having to bring my own from home, I want to have one at BSC. These
-are enough and come in a nice box so I don't lose them:
-
-<https://www.amazon.es/BLOSTM-Juego-Destornilladores-Profesionales-Destornillador/dp/B09W9R8J3S>
-
-## Serial port adaptor
-
-In order to debug problems with several components, we need to be able to plug
-to the serial port of the CPU. As we may deal with different voltages and
-pinouts, the most versatile option is to just be able to select the voltage and
-expose a pin interface.
-
-This one would do:
-
-<https://www.amazon.es/DSD-TECH-SH-U09C5-convertidor-Soporte/dp/B07WX2DSVB>
-
-## Storage for raccoon
-
-Given that we are currently using raccoon for builds too, we would need to
-increase its current storage. We only have available 270 GB, so we can benefit
-from another disk. Using 2 TiB would be plenty. This one seems enough:
-
-- 135,99€ <https://www.amazon.es/Crucial-BX500-pulgadas-interno-CT2000BX500SSD101/dp/B0CCN9QWKT>

m/common/base/nix.nix

@@ -23,7 +23,6 @@
       trusted-users = [ "@wheel" ];
       flake-registry = pkgs.writeText "global-registry.json"
         ''{"flakes":[],"version":2}'';
-      keep-outputs = true;
     };
 
     gc = {

m/common/base/ssh.nix

@@ -10,7 +10,7 @@ in
 
   # Connect to intranet git hosts via proxy
   programs.ssh.extraConfig = ''
-    Host bscpm02.bsc.es bscpm03.bsc.es bscpm04.bsc.es gitlab-internal.bsc.es alya.gitlab.bsc.es
+    Host bscpm02.bsc.es bscpm03.bsc.es gitlab-internal.bsc.es alya.gitlab.bsc.es
       User git
       ProxyCommand nc -X connect -x hut:23080 %h %p
 
@@ -22,7 +22,6 @@ in
   programs.ssh.knownHosts = hostsKeys // {
     "gitlab-internal.bsc.es".publicKey = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIF9arsAOSRB06hdy71oTvJHG2Mg8zfebADxpvc37lZo3";
     "bscpm03.bsc.es".publicKey = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIM2NuSUPsEhqz1j5b4Gqd+MWFnRqyqY57+xMvBUqHYUS";
-    "bscpm04.bsc.es".publicKey = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIPx4mC0etyyjYUT2Ztc/bs4ZXSbVMrogs1ZTP924PDgT";
     "glogin1.bsc.es".publicKey = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIFsHsZGCrzpd4QDVn5xoDOtrNBkb0ylxKGlyBt6l9qCz";
     "glogin2.bsc.es".publicKey = "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIFsHsZGCrzpd4QDVn5xoDOtrNBkb0ylxKGlyBt6l9qCz";
   };

m/common/xeon/net.nix

@@ -11,7 +11,7 @@
 
     proxy = {
       default = "http://hut:23080/";
-      noProxy = "127.0.0.1,localhost,internal.domain,10.0.40.40,hut";
+      noProxy = "127.0.0.1,localhost,internal.domain,10.0.40.40";
       # Don't set all_proxy as go complains and breaks the gitlab runner, see:
       # https://github.com/golang/go/issues/16715
       allProxy = null;

m/hut/configuration.nix

@@ -56,11 +56,6 @@
         iptables -A nixos-fw -p tcp -s 10.0.40.30 --dport 23080 -j nixos-fw-log-refuse
         iptables -A nixos-fw -p tcp -s 10.0.40.0/24 --dport 23080 -j nixos-fw-accept
       '';
-      # Flush all rules and chains on stop so it won't break on start
-      extraStopCommands = ''
-        iptables -F
-        iptables -X
-      '';
     };
   };
 

m/hut/gitlab-runner.nix

@@ -97,13 +97,12 @@
     };
   };
 
-  # DOCKER* chains are useless, override at FORWARD and nixos-fw
+  # DOCKER* chains are useless, override at FORWARD
   networking.firewall.extraCommands = ''
-    # Don't forward any traffic from docker
-    iptables -I FORWARD 1 -p all -i docker0 -j nixos-fw-log-refuse
-
-    # Allow incoming traffic from docker to 23080
-    iptables -A nixos-fw -p tcp -i docker0 -d hut --dport 23080 -j ACCEPT
+    # Allow docker to use our proxy
+    iptables -I FORWARD 1 -p tcp -i docker0 -d hut --dport 23080 -j nixos-fw-accept
+    # Block anything else coming from docker
+    iptables -I FORWARD 2 -p all -i docker0 -j nixos-fw-log-refuse
   '';
 
   #systemd.services.gitlab-runner.serviceConfig.Shell = "${pkgs.bash}/bin/bash";

m/hut/monitoring.nix

@@ -46,7 +46,7 @@
   services.prometheus = {
     enable = true;
     port = 9001;
-    retentionTime = "5y";
+    retentionTime = "1y";
     listenAddress = "127.0.0.1";
   };
 
@@ -250,14 +250,6 @@
           module = [ "raccoon" ];
         };
       }
-      {
-        job_name = "raccoon";
-        static_configs = [
-          {
-            targets = [ "127.0.0.1:19002" ]; # Node exporter
-          }
-        ];
-      }
       {
         job_name = "ipmi-fox";
         metrics_path = "/ipmi";

m/hut/nginx.nix

@@ -17,14 +17,13 @@ let
   };
 in
 {
-  networking.firewall.allowedTCPPorts = [ 80 ];
   services.nginx = {
     enable = true;
     virtualHosts."jungle.bsc.es" = {
       root = "${website}";
       listen = [
         {
-          addr = "0.0.0.0";
+          addr = "127.0.0.1";
           port = 80;
         }
       ];

m/module/hut-substituter.nix

@@ -4,7 +4,7 @@
     # Don't add hut as a cache to itself
     assert config.networking.hostName != "hut";
     {
-      substituters = [ "http://hut/cache" ];
+      substituters = [ "https://jungle.bsc.es/cache" ];
       trusted-public-keys = [ "jungle.bsc.es:pEc7MlAT0HEwLQYPtpkPLwRsGf80ZI26aj29zMw/HH0=" ];
     };
 }

m/raccoon/configuration.nix

@@ -3,6 +3,7 @@
 {
   imports = [
     ../common/base.nix
+    ../module/hut-substituter.nix
   ];
 
   # Don't install Grub on the disk yet
@@ -25,11 +26,6 @@
     } ];
   };
 
-  nix.settings = {
-    substituters = [ "https://jungle.bsc.es/cache" ];
-    trusted-public-keys = [ "jungle.bsc.es:pEc7MlAT0HEwLQYPtpkPLwRsGf80ZI26aj29zMw/HH0=" ];
-  };
-
   # Configure Nvidia driver to use with CUDA
   hardware.nvidia.package = config.boot.kernelPackages.nvidiaPackages.production;
   hardware.graphics.enable = true;

web/content/hut/_index.md

@@ -57,7 +57,7 @@ Note: you'll have to be a trusted user.
 
 ### Nix configuration file (non-nixos)
 
-If using nix outside of NixOS, you'll have to update `/etc/nix/nix.conf`
+If using nix outside of NixOS, you'll have to update `nix.conf`
 
 ```
 # echo "substituters = https://jungle.bsc.es/cache" >> /etc/nix/nix.conf