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Contemporary African Music is not getting the credit it deserves

I am on a binge, listening to tons of Nigerian, Ugandan and Kenian music, and I am absolutely loving it. Why is this not playing on our (Western European) radio stations regularly?

Instead I have to regularly change stations because someone is trying to torture my ears with Ed Sheeran or similar BS. :(

8
Listen to a genius, kids.
  • I see no problem here: I refused to serve in the military and did my service in a hospital instead. The Ukraine war did make me reconsider my attitude towards the necessity of a draft army.

    Conclusion 1: I would emigrate and work against my country of origin in a heartbeat if they started a war of aggression (hello Russians) - unchanged from before

    Conclusion 2: I would support with my medical and other skills those defending a non-aggressive country I live in

    Conclusion 3: I might fight, given no other choice. But I would try everything else first, and I would probably not be good at it (fighting) at all.

  • Google ad on a magazine from 1999
  • I wouldn't be surprised if there was some kind of Steve Wozniak / Steve Jobs split personality thing going on. Maybe one or the other person involved were serious about the "don't be evil" thing. But the others were not.

  • Erlangen: "Ausländer raus"-Rufe auf Bergkirchweih: Staatsschutz ermittelt
  • Dieser miese Haufen kleinhirniger Drecksnazis - ich kann gar nicht so viel fressen, wie ich kotzen will. Wie dummbratzig kann man eigentlich sein, ohne das Atmen zu vergessen? FCK AFD. Und das ganze "konservative" Dreckspack mit seinem rassistischen Pfeifenblasen gleich mit - ja, auch die rote Sahra.

  • A mink farm in Denamrk
  • Tone may not be okay, the question I am asking is: is it worth that people like you and me waste our time arguing over whether or not we should care? For me, personally, as long as someone doesn't dehumanize other people or call for violence, I am comfy ignoring their rants if I feel they are insubstantial.

  • My potato had a mushroom shaped internal cavity

    Hadn't seen this before - I wonder if that was once on the potato outside and then grew closed?

    15
    Kriegsdienstverweigerung 1994

    Ich bin nicht mit Allem einverstanden, was mein 18-jähriges Ich verbrochen hat, aber für diese Gewissenserklärung werde ich mich niemals schämen.

    41
    Getting started with net-snmp in C++

    Hey everyone! I wanted to post my guide / experiences from the past years here - this is not strictly Zabbix, but SNMP (which Zabbix could monitor), and in C++, but I think given that lemmy isn't yet huge, I'd rather have the post in a space with more topics, than an isolated 1-user-community. See below.

    End 2022, I had finally gotten around to creating a standalone SNMP agent with a lot of demo-functionality. I will post the link / instructions for that in a separate comment below.

    #Getting started with net-snmp in C++ ------------- I am trying to work myself into the use of net-snmp (on a Linux system, but ideally in a way compatible to mingw/gcc on Windows). Unfortunately, the net-snmp documentation as per http://www.net-snmp.org/ seems to be very lacking. There are coding tutorials, which at some point refer you to an empty section in the wiki that you "should read before continuing" (This one here: Writing_a_MIB_Module). So I am down to a lot of web (re)searching and trial & error.

    The aim of this post is to end up with a step-by-step approach that accomplishes the following:

    • Installation & configuration of all required software packages on a debian system (for starters)
    • Clarification of the relevant snmp terminology used in this step-by-step guide
    • Making the example executables (or modified versions thereof) from the net-snmp.org coding tutorials work to
      • request a specific value by existing snmp object identifiers (OIDs) with a targeted instruction
      • request a list of OIDs listed in an array, from multiple hosts
      • create & use a custom management information base (MIB)
      • create a custom snmp agent that can serve requests for OIDs defined in that custom MIB
      • create a simple monitoring application that can cyclically request certain OIDs from the custom agent

    The final demo implementation will be a "hello world" of sorts for SNMP, wherein the custom snmp agent reports it's application "health" (e.g. process id, process name, a timestamp and a cyclic counter / heartbeat) via the custom MIB, and the monitoring application monitors the health of that custom agent on the console (as opposed to having to set up s.t. more complicated like zabbix).

    Please bear with me, as I am stuck on the custom agent for now. I have to solve this problem, however, and I will update this post with my solution. Help is very much appreciated!

    So - without further ado, here is my current status:

    Package installation: ```

    force installation of snmpd with default /etc/snmp/snmpd.conf

    sudo apt install --reinstall -o Dpkg::Options::="--force-confask,confnew,confmiss" snmpd

    force installation of default /etc/snmp/snmp.conf

    sudo apt install --reinstall -o Dpkg::Options::="--force-confask,confnew,confmiss" libsnmp-base

    install snmp and snmp-mibs-downloader

    sudo aptitude install snmp snmp-mibs-downloader

    Note: former net-snmp-utils files are now all included in package snmp

    ```

    Package configuration: ```

    comment out the "mibs :" line in snmp.conf (TBC: forgot why I did this :( )

    sudo sed -i 's/^mibs :$/#mibs :/' /etc/snmp/snmp.conf

    nothing else for the moment

    Activate configuration changes (if any) sudo /etc/init.d/snmpd restart #Test package configuration: snmpwalk -v 2c -c public localhost

    a bunch of output about localhost will follow

    ``` Explanation: snmpwalk checks the destination (localhost) for all available OIDs and requests them once.

    Note: Option values can be separated by space or not at all, so -v 1 and -v1 is equivalent.

    Option -v is the snmp protocol version, -v1 or -v2c work. Disclaimer: -v3 requires authentication logic that I have not yet figured out. Option -c sets the "community" string - which I have not quite figured out yet, but "public" is good for accessing OIDs that do not require a password.

    Speculation: I believe the community string is simply correlated to how certain OIDs are registered in the snmp master agent (daemon) and you can only access them through the configured community.

    Manual request of an OID on the command line: snmptest -v 2c -c public localhost This will open a request prompt, on which you can enter the OID / variable identifier of anything you previously saw on the output of snmpwalk. Multiple variables can be requested at once. E.g.: Variable: SNMPv2-MIB::sysDescr.0 Variable: SNMPv2-MIB::sysORID.1 Variable: In order to submit (send) the request, you have to enter an empty line. When you are done, exit snmptest with CTRL-C. Now that we are done with the installation & configuration, it is time to get the demo applications running.

    Getting ready for the net-snmp coding tutorial:

    I have downloaded the following files from the coding tutorial subsections here: asyncapp.c example-daemon.c # called example-demon.c there, I renamed it Makefile NET-SNMP-TUTORIAL-MIB.txt nstAgentModuleObject.c nstAgentModuleObject.h nstAgentPluginObject.c nstAgentPluginObject.h nstAgentSubagentObject.c nstAgentSubagentObject.h snmpdemoapp snmpdemoapp.c These files were not created by me and I take no credit for them. I have, however, modified these files to fit my personal preference of C code formatting, and to add comments and better understand what is going on - and also to fix some incompatibilities with my system and change them to use SNMP_VERSION_2c so I could get a working software before I have to study the authentication logic of version 3.

    I have uploaded my modified version of the tutorial files here (link valid only until 2020-05-20, I'll upload it elsewhere if someone knows a good free filehoster): 2020-05-06-net-snmp-coding-tutorial.tgz

    Please review the code before compiling stuff some random stranger gave you ;)

    You need to copy the tutorial MIB file to a place where your snmpd (the master agent) will find it: sudo cp NET-SNMP-TUTORIAL-MIB.txt /usr/share/snmp/mibs/

    Testing whether the MIB file is found by the snmp applications: ```

    snmptranslate -m +NET-SNMP-TUTORIAL-MIB -IR -On nstAgentModuleObject

    (the above has the same effect as the below)

    snmptranslate -On NET-SNMP-TUTORIAL-MIB::nstAgentModuleObject ```

    This should output .1.3.6.1.4.1.8072.2.4.1.1.1

    Compiling and executing the tutorial files:

    Disclaimer: As of today (2020-05-05), I have only managed to successfully use the snmpdemoapp and the asyncapp - the other apps are still untested / non-functional in this version.

    When you execute "make" in the folder with your source files & the Makefile, you will get two warnings example-daemon.c:50:3: warning: implicit declaration of function ‘init_vacm_vars’; did you mean ‘init_vacm’? [-Wimplicit-function-declaration] init_vacm_vars(); ^~~~~~~~~~~~~~ init_vacm example-daemon.c:51:3: warning: implicit declaration of function ‘init_usmUser’; did you mean ‘init_usm’? [-Wimplicit-function-declaration] init_usmUser(); ^~~~~~~~~~~~ init_usm I have not yet figured out if this code is intentionally referring to unknown functions, and whether or not this is functional or a failure. Let's ignore it for now.

    After building the executables, you can test: ./snmpdemoapp SNMPv2-MIB::sysORDescr.3 = STRING: The SNMP Management Architecture MIB. value #1 is a string: The SNMP Management Architecture MIB. and ./asyncapp ---------- synchronous ----------- 23:25:47.095474 localhost: SNMPv2-MIB::sysDescr.0 = STRING: Linux YOURHOSTNAME <YOUR OS VERSION AND ARCHITECTURE> 23:25:47.095637 localhost: SNMPv2-MIB::sysORDescr.1 = STRING: The MIB for Message Processing and Dispatching. 23:25:47.095758 localhost: SNMPv2-MIB::sysORDescr.2 = STRING: The management information definitions for the SNMP User-based Security Model. 23:25:47.095961 localhost: SNMPv2-MIB::sysDescr.0 = STRING: Linux YOURHOSTNAME <YOUR OS VERSION AND ARCHITECTURE> 23:25:47.096076 localhost: SNMPv2-MIB::sysORDescr.1 = STRING: The MIB for Message Processing and Dispatching. 23:25:47.096199 localhost: SNMPv2-MIB::sysORDescr.2 = STRING: The management information definitions for the SNMP User-based Security Model. ---------- asynchronous ----------- 23:25:47.096538 localhost: SNMPv2-MIB::sysDescr.0 = STRING: Linux YOURHOSTNAME <YOUR OS VERSION AND ARCHITECTURE> 23:25:47.096657 localhost: SNMPv2-MIB::sysDescr.0 = STRING: Linux YOURHOSTNAME <YOUR OS VERSION AND ARCHITECTURE> 23:25:47.096769 localhost: SNMPv2-MIB::sysORDescr.1 = STRING: The MIB for Message Processing and Dispatching. 23:25:47.096877 localhost: SNMPv2-MIB::sysORDescr.1 = STRING: The MIB for Message Processing and Dispatching. 23:25:47.096986 localhost: SNMPv2-MIB::sysORDescr.2 = STRING: The management information definitions for the SNMP User-based Security Model. 23:25:47.097036 localhost: SNMPv2-MIB::sysORDescr.2 = STRING: The management information definitions for the SNMP User-based Security Model.

    Now you can modify the snmpdemoapp.c and the asyncapp.c to include / request different hosts / OIDs. Please note that I have requested the same OIDs from localhost twice in asyncapp.c to allow this tutorial executable to function without any further host ready on the network and to demonstrate the sync vs. async behavior.

    Edit 2020-05-06: Progress - I got a subagent registered (for now, only as root user :( ) and running as expected:

    Configure a community "tutorial" that we can use to access our tutorial MIB ```

    configuring a community with access rights to custom MIB(s)

    Source: https://unix.stackexchange.com/questions/463969/snmp-no-such-object-available-on-this-agent-at-this-oid

    it appears that the common path is .1.3.6.1 and then custom MIBs have the .4 branch (TBC)

    add a custom community permitting read access to our tutorial MIB

    echo "" > new-communities-for-snmpd.conf echo "# custom communities" >> new-communities-for-snmpd.conf echo "rocommunity tutorial 127.0.0.1 .1.3.6.1.4 # TBC: branch for custom mibs" >> new-communities-for-snmpd.conf cat new-communities-for-snmpd.conf | sudo tee -a /etc/snmp/snmpd.conf rm new-communities-for-snmpd.conf ```

    Restart the snmpd daemon to load the new config: sudo service snmpd restart

    Build tutorial executables: make

    Attempt to retrieve an OID handled by the example daemon snmpget -v 2c -c tutorial localhost NET-SNMP-TUTORIAL-MIB::nstAgentSubagentObject.0

    Since the daemon is not yet running, this will fail: "NET-SNMP-TUTORIAL-MIB::nstAgentSubagentObject.0 = No Such Object available on this agent at this OID"

    Start the tutorial subagent: sudo ./example-daemon -f

    Open a second console and attempt to retrieve the OID as above: snmpget -v 2c -c tutorial localhost NET-SNMP-TUTORIAL-MIB::nstAgentSubagentObject.0

    This time, the request should succeed: "NET-SNMP-TUTORIAL-MIB::nstAgentSubagentObject.0 = INTEGER: 2"

    Check the first terminal (where the example-daemon is running), it should say

    hello world!

    This message was triggered by the handler function handler_nstAgentSubagentObject installed in nstAgentSubagentObject.c ``` /* Function: handler_nstAgentSubagentObject

    • Purpose: callback handler for the request to an OID of this subagent

    */ int handler_nstAgentSubagentObject( netsnmp_mib_handler *mibHandler, netsnmp_handler_registration *handlerRegistration, netsnmp_agent_request_info *agentRequestInfo, netsnmp_request_info *requestInfo ) { printf( "hello world!\n" );

    return 0; } ```

    The handler function is registered as a callback handler in the call to netsnmp_register_long_instance.

    From here on, this is all work in progress. Next steps:

    • create a handler routine that will work with snmpwalk & allow to see all OIDs identified for a certain community
    • create a custom MIB with sample application telemetry
    • create a handler routine that will update the OID values as part of the snmp agent (e.g. by interacting with a separate application thread that keeps updated telemetry in a struct)
    • create a monitoring application that periodically checks the content of the custom MIB and displays it on the console
    • somewhere along the way: figure out how to run all this as non-root user!!

    I stand by my original comment: The state of documentation of this de-facto standard in worldwide networking equipment has me baffled. It is embarrassingly shitty.

    1
    InitialsDiceBearhttps://github.com/dicebear/dicebearhttps://creativecommons.org/publicdomain/zero/1.0/„Initials” (https://github.com/dicebear/dicebear) by „DiceBear”, licensed under „CC0 1.0” (https://creativecommons.org/publicdomain/zero/1.0/)RA
    raspberriesareyummy @lemmy.world
    Posts 4
    Comments 635