Entries by Raymond P. Burkholder

• What is Kubernetes and how should you monitor it? - A monitoring strategy that takes advantage of Kubernetes will give you a bird's eye view of your entire application’s performance, even if containers running your applications are continuously moving between hosts or being scaled up and down.
• How to optimize Kubernetes resource configurations for cost and performance - in part two of this Kubernetes guide, you'll get help balancing appropriate parameter configuration for any cluster you are working with now or in the future. You'll learn about requests and limits, measuring CPU utilization, and how to optimize Kubernetes resource allocation.
• Best way to install and use kubernetes for learning - reddit
• Kubernetes The Hard Way - This tutorial walks you through setting up Kubernetes the hard way. This guide is not for people looking for a fully automated command to bring up a Kubernetes cluster. Kubernetes The Hard Way is optimized for learning, which means taking the long route to ensure you understand each task required to bootstrap a Kubernetes cluster.
• Deploying a Kubernetes Cluster within Proxmox using Ansible

• A capable attacker will look for plaintext
• red/black separation
• Schneiers's principle
• Zooko's tradeoff
• Kerckhoffs's Principle
• Corollary to Metcalfe's principle [2]
• It is easier for insiders to steal information - also janitors, cleaners
• Design for known threats
• Design for future threats
• Design for unknown threats as far as possible
• existing systems persist
• defence in depth
• monoculture -> target more attractive, usually more brittle
• the capital and operating costs of well-designed secure systems are about the same as those of insecure ones until the insecure ones fail
• keep intrusion records
• keep i/o records
• cheap and effective security needs good system design.
• if it's expensive, it probably won't be effective.
• Unless it is for your use alone you do not control what a system is to be used for
• Even if it is for your use alone you do not control the resources which will be pitted against your system
• cryptanalysis is difficult - but people can do difficult things
• people offering the impossible are lying
• in code, nothing ever really goes away

The principles can sometimes be broken or wrong, unlike the laws.

[2] the security of a secret is inversely proportional to the square of the number of people who know it

- Peter Fairbrother

0. It's all about who is in control
1. Someone else is after the things you have
2. An attacker can't steal things which aren't there to steal
3. Everywhere can be attacked
4. More complex systems provide more places to attack
5. Attack methods are many, varied, ever-changing and eternal
6. Only those you trust can betray you
7. Holes for good guys are holes for bad guys too
8. A system which is hard to use will be misused, abused and underused
9. Security is a Boolean. [1]
10. Items of data once publicly linked cannot be reliably unlinked

[1] Looking back in time from the future - did it work? Then it was secure enough. Can be hard to see that from the present though, and even from the future not all harmful breaches can be seen.

- Peter Fairbrother

Source: What Is PCIe Card? Everything You Need to Know About PCI Express Card

Take a look at Introduction to Linux Interrupts and CPU SMP Affinity. Controlling Core Assignments

ps aux |grep irq
irqbalance
cat /proc/interrupts

Algorithmic Trading Using Continuous Action Space Deep Reinforcement Learning

Price movement prediction has always been one of the traders' concerns in financial market trading. In order to increase their profit, they can analyze the historical data and predict the price movement. The large size of the data and complex relations between them lead us to use algorithmic trading and artificial intelligence.

This paper aims to offer an approach using Twin-Delayed DDPG (TD3) and the daily close price in order to achieve a trading strategy in the stock and cryptocurrency markets. Unlike previous studies using a discrete action space reinforcement learning algorithm, the TD3 is continuous, offering both position and the number of trading shares. Both the stock (Amazon) and cryptocurrency (Bitcoin) markets are addressed in this research to evaluate the performance of the proposed algorithm.

The achieved strategy using the TD3 is compared with some algorithms using technical analysis, reinforcement learning, stochastic, and deterministic strategies through two standard metrics, Return and Sharpe ratio. The results indicate that employing both position and the number of trading shares can improve the performance of a trading system based on the mentioned metrics.

Swarm of UAVs for Network Management in 6G: A Technical Review

Fifth-generation (5G) cellular networks have led to the implementation of beyond 5G (B5G) networks, which are capable of incorporating autonomous services to swarm of unmanned aerial vehicles (UAVs). They provide capacity expansion strategies to address massive connectivity issues and guarantee ultra-high throughput and low latency, especially in extreme or emergency situations where network density, bandwidth, and traffic patterns fluctuate. On the one hand, 6G technology integrates AI/ML, IoT, and blockchain to establish ultra-reliable, intelligent, secure, and ubiquitous UAV networks. 6G networks, on the other hand, rely on new enabling technologies such as air interface and transmission technologies, as well as a unique network design, posing new challenges for the swarm of UAVs. Keeping these challenges in mind, this article focuses on the security and privacy, intelligence, and energy-efficiency issues faced by swarms of UAVs operating in 6G mobile networks. In this state-of-the-art review, we integrated blockchain and AI/ML with UAV networks utilizing the 6G ecosystem. The key findings are then presented, and potential research challenges are identified. We conclude the review by shedding light on future research in this emerging field of research.

Perspectives on a 6G Architecture

Mobile communications have been undergoing a generational change every ten years. Whilst we are just beginning to roll out 5G networks, significant efforts are planned to standardize 6G that is expected to be commercially introduced by 2030. This paper looks at the use cases for 6G and their impact on the network architecture to meet the anticipated performance requirements. The new architecture is based on integrating various network functions in virtual cloud environments, leveraging the advancement of artificial intelligence in all domains, integrating different sub-networks constituting the 6G system, and on enhanced means of exposing data and services to third parties.

On Routing Optimization in Networks with Embedded Computational Services

Modern communication networks are increasingly equipped with in-network computational capabilities and services. Routing in such networks is significantly more complicated than the traditional routing. A legitimate route for a flow not only needs to have enough communication and computation resources, but also has to conform to various application-specific routing constraints. This paper presents a comprehensive study on routing optimization problems in networks with embedded computational services. We develop a set of routing optimization models and derive low-complexity heuristic routing algorithms for diverse computation scenarios. For dynamic demands, we also develop an online routing algorithm with performance guarantees. Through evaluations over emerging applications on real topologies, we demonstrate that our models can be flexibly customized to meet the diverse routing requirements of different computation applications. Our proposed heuristic algorithms significantly outperform baseline algorithms and can achieve close-to-optimal performance in various scenarios.

Network Intrusion Detection System in a Light Bulb

Internet of Things (IoT) devices are progressively being utilised in a variety of edge applications to monitor and control home and industry infrastructure. Due to the limited compute and energy resources, active security protections are usually minimal in many IoT devices. This has created a critical security challenge that has attracted researchers' attention in the field of network security. Despite a large number of proposed Network Intrusion Detection Systems (NIDSs), there is limited research into practical IoT implementations, and to the best of our knowledge, no edge-based NIDS has been demonstrated to operate on common low-power chipsets found in the majority of IoT devices, such as the ESP8266. This research aims to address this gap by pushing the boundaries on low-power Machine Learning (ML) based NIDSs. We propose and develop an efficient and low-power ML-based NIDS, and demonstrate its applicability for IoT edge applications by running it on a typical smart light bulb. We also evaluate our system against other proposed edge-based NIDSs and show that our model has a higher detection performance, and is significantly faster and smaller, and therefore more applicable to a wider range of IoT edge devices.

using ip link in brief mode:

# ip -br link
lo               UNKNOWN        00:00:00:00:00:00 
eno1             UP             c8:1f:66:ea:43:20 
eno2             UP             c8:1f:66:ea:43:21 
eno3             UP             c8:1f:66:ea:43:22 
eno4             DOWN           c8:1f:66:ea:43:23 

using ip addr in brief mode:

# ip -br a
lo               UNKNOWN        127.0.0.1/8 10.32.0.12/32 ::1/128
eno1             UP
eno2             UP
eno3             UP             10.32.3.12/24 fe80::ca1f:66ff:feea:4322/64
eno4             DOWN

Access to the SFP style:

# ethtool -m enp65s0f0np0
Identifier                                : 0x03 (SFP)
Extended identifier                       : 0x04 (GBIC/SFP defined by 2-wire interface ID)
Connector                                 : 0x23 (No separable connector)
Transceiver codes                         : 0x01 0x00 0x00 0x04 0x00 0x04 0x00 0x00 0x0d
Transceiver type                          : Infiniband: 1X Copper Passive
Transceiver type                          : Ethernet: 1000BASE-CX
Transceiver type                          : Passive Cable
Transceiver type                          : Extended: 25G Base-CR CA-N
Encoding                                  : 0x06 (64B/66B)
BR, Nominal                               : 25750MBd
Rate identifier                           : 0x00 (unspecified)
Length (SMF,km)                           : 0km
Length (SMF)                              : 0m
Length (50um)                             : 0m
Length (62.5um)                           : 0m
Length (Copper)                           : 1m
Length (OM3)                              : 0m
Passive Cu cmplnce.                       : 0x01 (SFF-8431 appendix E) [SFF-8472 rev10.4 only]
Vendor name                               : Mellanox
Vendor OUI                                : 00:02:c9
Vendor PN                                 : MCP2M00-A001E30N
Vendor rev                                : A4
Option values                             : 0x00 0x00
BR margin, max                            : 0%
BR margin, min                            : 0%
Vendor SN                                 : MT2010VB00194
Date code                                 : 200219
Optical diagnostics support               : No

driver and firmware info:

# ethtool -i enp65s0f0np0
driver: mlx5_core
version: 5.15.39-4-pve
firmware-version: 16.34.1002 (MT_0000000183)
expansion-rom-version:
bus-info: 0000:41:00.0
supports-statistics: yes
supports-test: yes
supports-eeprom-access: no
supports-register-dump: no
supports-priv-flags: yes

Show ethernet controllers on the pci bus:

# lspci |grep -i ether
01:00.0 Ethernet controller: Intel Corporation I350 Gigabit Network Connection (rev 01)
01:00.1 Ethernet controller: Intel Corporation I350 Gigabit Network Connection (rev 01)
01:00.2 Ethernet controller: Intel Corporation I350 Gigabit Network Connection (rev 01)
01:00.3 Ethernet controller: Intel Corporation I350 Gigabit Network Connection (rev 01)
42:00.0 Ethernet controller: Mellanox Technologies MT27800 Family [ConnectX-5]
42:00.1 Ethernet controller: Mellanox Technologies MT27800 Family [ConnectX-5]

Show details on a specific ethernet controller:

# lspci -vvnn -s 42:00.0
42:00.0 Ethernet controller [0200]: Mellanox Technologies MT27800 Family [ConnectX-5] [15b3:1017]
Subsystem: Mellanox Technologies MT27800 Family [ConnectX-5] [15b3:0061]
Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- SERR- 

Show a tree of entries (output is clipped):

~# lspci -tvnn
-+-[0000:7f]-+-08.0  Intel Corporation Xeon E7 v2/Xeon E5 v2/Core i7 QPI Link 0 [8086:0e80]
|           +-09.0  Intel Corporation Xeon E7 v2/Xeon E5 v2/Core i7 QPI Link 1 [8086:0e90]
.....

Show available physical slots and their capability:

# dmidecode -t 9
# dmidecode 3.3
Getting SMBIOS data from sysfs.
SMBIOS 2.7 present.

Handle 0x0900, DMI type 9, 17 bytes
System Slot Information
Designation: PCI1
Type: x8 PCI Express 3 x16
Current Usage: Available
Length: Long
ID: 1
Characteristics:
3.3 V is provided
PME signal is supported

Handle 0x0901, DMI type 9, 17 bytes
System Slot Information
Designation: PCI2
Type: x16 PCI Express 3
Current Usage: In Use
Length: Long
ID: 2
Characteristics:
3.3 V is provided
PME signal is supported
Bus Address: 0000:42:00.0

Handle 0x0902, DMI type 9, 17 bytes
System Slot Information
Designation: PCI3
Type: x16 PCI Express 3
Current Usage: Available
Length: Long
ID: 3
Characteristics:
3.3 V is provided
PME signal is supported

But what is actually negotiated might be different:

root@host01:~# lspci -vvnn -s 42:00.0|grep Lnk
LnkCap: Port #0, Speed 8GT/s, Width x16, ASPM not supported
LnkCtl: ASPM Disabled; RCB 64 bytes, Disabled- CommClk+
LnkSta: Speed 5GT/s (downgraded), Width x16 (ok)
LnkCap2: Supported Link Speeds: 2.5-8GT/s, Crosslink- Retimer- 2Retimers- DRS-
LnkCtl2: Target Link Speed: 8GT/s, EnterCompliance- SpeedDis-
LnkSta2: Current De-emphasis Level: -6dB, EqualizationComplete+ EqualizationPhase1+
LnkCtl3: LnkEquIntrruptEn- PerformEqu-

On one slot, I get 'LnkSta: Speed 8GT/s (ok), Width x8 (downgraded)' [8GT/s * x8 = 64], and in another slot it have "Speed 5GT/s (downgraded), Width x16 (ok)' [5GT/s * x16 = 80], so I guess we use x16 slot.

List kernel drivers for a specific pci slot:

# lspci -k -s 42:00
42:00.0 Ethernet controller: Mellanox Technologies MT27800 Family [ConnectX-5]
Subsystem: Mellanox Technologies MT27800 Family [ConnectX-5]
Kernel driver in use: mlx5_core
Kernel modules: mlx5_core
42:00.1 Ethernet controller: Mellanox Technologies MT27800 Family [ConnectX-5]
Subsystem: Mellanox Technologies MT27800 Family [ConnectX-5]
Kernel driver in use: mlx5_core
Kernel modules: mlx5_core

Show details for a specific kernel module:

# modinfo mlx5_core
filename:       /lib/modules/5.15.39-4-pve/kernel/drivers/net/ethernet/mellanox/mlx5/core/mlx5_core.ko
license:        Dual BSD/GPL
description:    Mellanox 5th generation network adapters (ConnectX series) core driver
author:         Eli Cohen 
srcversion:     8802C9A5BF30F219CD73715
alias:          auxiliary:mlx5_core.eth
....
alias:          auxiliary:mlx5_core.eth-rep
alias:          auxiliary:mlx5_core.sf
depends:        tls,pci-hyperv-intf,mlxfw,psample
retpoline:      Y
intree:         Y
name:           mlx5_core
vermagic:       5.15.39-4-pve SMP mod_unload modversions
parm:           debug_mask:debug mask: 1 = dump cmd data, 2 = dump cmd exec time, 3 = both. Default=0 (uint)
parm:           prof_sel:profile selector. Valid range 0 - 2 (uint)

• Understanding PCIe Configuration for Maximum Performance

The dummy interface is not used in the actual routing process in most cases. The dummy ip address is inserted into the local route table as a local address (check it out yourself: ip ro sh table local). Ingress packets from all interfaces are checked against this table first (as it is the maximum priority rule in the ip rule), and if a local-type route matches, the packet is queued for local delivery. Egress packets are even simpler: your default route will point towards your physical interface; the packets will be queued directly to that interface's queues and you'll keep all your regular GSOs and GROs -- at least the ones that are managed by the kernel.

There are standard ways many nics can offload packets: TSO (tcp segment offloading), gso (generic segment offloading), gro (generic receive offload), lro (large receive offload) are the common ones. You can see which ones are enabled with ethtool -k interface_name, interface usually has to be down to change them.

$ sudo df -Tlh
Filesystem     Type      Size  Used Avail Use% Mounted on
udev           devtmpfs   16G     0   16G   0% /dev
tmpfs          tmpfs     3.2G  1.6M  3.2G   1% /run
/dev/nvme0n1p4 btrfs      94G  6.8G   85G   8% /
tmpfs          tmpfs      16G   85M   16G   1% /dev/shm
tmpfs          tmpfs     5.0M  4.0K  5.0M   1% /run/lock
/dev/nvme0n1p6 btrfs      94G  898M   91G   1% /usr/local
/dev/nvme0n1p7 btrfs     187G   14G  172G   8% /var
...

Admin magazine has an article called Create secure simple containers with the systemd tools Nspawnd and Portabled, which offers a mechanism different from my favorite LXC mechanisms. I'll have to give it a try for simpler projects.

They seem to be subsets of the templates and caching already available via LXC, but the one stand out is an added tool called mkosi, which stands for Make Operating System Image, and is a tool for precisely that: generating an OS tree or image that can be booted. It seems to be useful for creating container images as well as images which can be used in heavier virtualization environments such as KVM.

From Using a "proper" camera as a webcam there were some references to some interesting inexpensive high resolution cameras and lenses. I can't vouch for quality, but I intend to give them a try.

• C920/C922/C930 enclosure kit for CS-type lens mk2 - with some references to lenses and IR-cut filters
• IMX477 Full Report – Datasheet, Specs, Technologies and Camera Modules - f you are considering the Sony IMX477 or IMX477R, then this is for you. datasheets, specs, and related informaiton
• ArduCam embedded camera solutions on Amazon

There are suggestions for teleprompters in there as well.

Interesting portions of the query:

# decode-dimms 
# decode-dimms version 4.3

Memory Serial Presence Detect Decoder
By Philip Edelbrock, Christian Zuckschwerdt, Burkart Lingner,
Jean Delvare, Trent Piepho and others


Decoding EEPROM: /sys/bus/i2c/drivers/ee1004/3-0050
Guessing DIMM is in                              bank 1
Kernel driver used                               ee1004

---=== SPD EEPROM Information ===---
EEPROM CRC of bytes 0-125                        OK (0xB200)
# of bytes written to SDRAM EEPROM               384
Total number of bytes in EEPROM                  512
Fundamental Memory type                          DDR4 SDRAM
SPD Revision                                     1.1
Module Type                                      SO-DIMM
EEPROM CRC of bytes 128-253                      OK (0x2A87)

---=== Memory Characteristics ===---
Maximum module speed                             2400 MT/s (PC4-19200)
Size                                             16384 MB
Banks x Rows x Columns x Bits                    16 x 16 x 10 x 64
SDRAM Device Width                               8 bits
Ranks                                            2
Rank Mix                                         Symmetrical
Primary Bus Width                                64 bits
AA-RCD-RP-RAS (cycles)                           14-14-14-35
Supported CAS Latencies                          16T, 15T, 14T, 13T, 12T, 11T, 9T

---=== Manufacturer Data ===---
Module Manufacturer                              Kingston
DRAM Manufacturer                                SK Hynix (former Hyundai Electronics)
Manufacturing Location Code                      0x01
Manufacturing Date                               2018-W21
Assembly Serial Number                           0xC22D6945
Part Number                                      KHX2400C14S4/16G


Number of SDRAM DIMMs detected and decoded: 1
                           

IATA airport codes to LOC:

$ dig +short YYC.air.jpmens.net LOC
51 6 50.037 N 114 1 11.988 W 1084.00m 1m 10000m 10m

and more fun with an associated TXT:

$ dig +short YYC.air.jpmens.net TXT
"cc:CA; m:Calgary; t:large, n:Calgary International Airport"

with more at Airports of the world, and other data in DNS

Another from the email list (2022/04/22):

systemd-resolved is broken in many ways. I doubt it can forward correctly TSIG or SIG(0). If you have a proper DNS server running on your machine, there is not many reasons to run also systemd-resolved. If you need it, I suggest to write fixed /etc/resolv.conf pointing to 127.0.0.1 or ::1. Consider chattr +i /etc/resolv.conf afterwards. Do not use stub resolver provided by systemd if you have better caching server running on the same machine. I would even recommend to uninstall it on Fedora, where it is possible. Unless you use mdns on selected networks only, I don't think systemd-resolved provides you any benefit.

systemd-resolved strips in default configuration even DNSSEC signatures. I would doubt it can handle key signatures or even updates.

A solution:

    sudo systemctl disable systemd-resolved.service
    sudo service systemd-resolved stop

And then mask: systemd masking