• How to Keep Your Mac Awake for Long-Running Agent Tasks

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    kayama

    I usually run coding agents somewhere in a VM or on a remote host, so I don’t have to think about what my laptop is doing.

    But sometimes, especially for bigger tasks, I need to run an agent locally on my Mac.
    And then there is one annoying problem: macOS may go to sleep while the agent is still working.

    Apparently, caffeinate is a very simple way to prevent that.

    Keep the Mac awake for a specific amount of time:

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    caffeinate –t 3600
     

    This keeps it awake for 1 hour (3600 seconds).

    For a quick test:

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    time caffeinate –t 10
     

    And if you want to prevent pretty much all kinds of idle sleep while the command is running:

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    caffeinate –dimsu
     

    Simple, built into macOS, and surprisingly useful when running long AI agent tasks, builds, migrations, or anything else you don’t want interrupted by sleep.

  • Fast switch Terraform version

    kayama

    Very useful command: tfswitch

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    brew install warrensbox/tap/tfswitch

  • How to label Kubernetes node ROLE name

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    kayama

    That’s easy!

    Add Label:

    kubectl label node <node name> node-role.kubernetes.io/<role name>=<key — (any name)>

    Remove label:

    kubectl label node <node name> node-role.kubernetes.io/<role name>-

    Let’s try:

    $ kubectl get nodes

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    NAME                STATUS   ROLES                         AGE   VERSION
    node-1.domain.loc   Ready    master                        51d   v1.17.0
    node-2.domain.loc   Ready    <none>                        51d   v1.17.0
    node-3.domain.loc   Ready    <none>                        51d   v1.17.0

    $ kubectl label node node-2.domain.loc node-role.kubernetes.io/worker=

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    node/node-2.domain.loc labeled

    and check:

    $ kubectl get nodes

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    NAME                STATUS   ROLES                         AGE   VERSION
    node-1.domain.loc   Ready    master                        51d   v1.17.0
    node-2.domain.loc   Ready    worker                        51d   v1.17.0
    node-3.domain.loc   Ready    <none>                        51d   v1.17.0

  • How to setup L2TP over IPSec VPN server (Ubuntu 16.04 – 20.04)

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    kayama

    How to setup L2TP over IPSec VPN server (Ubuntu 16.04)

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    apt-get install strongswan xl2tpd

    # (optional, need to check ) apt-get install ppp libgmp3-dev bison flex

    Edit /etc/ipsec.conf

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    # /etc/ipsec.conf — Openswan IPsec configuration file modified for Strongswan
    # (c) Kayama 2018
    # Add connections here
     
    conn L2TP-IPSEC
        authby=secret
        rekey=no
        keyingtries=3
        type=transport
        esp=aes128-sha1
        ike=aes128-sha-modp1024
        ikelifetime=8h
        keylife=1h
        left=XXX.XXX.XXX.XXX # your router’s external IP 
        leftprotoport=17/1701
        right=%any
        rightprotoport=17/%any
        rightsubnet=0.0.0.0/0
        auto=add
        dpddelay=30
        dpdtimeout=120
        dpdaction=clear
        #force all to be nat’ed. because of iOS
        forceencaps=yes

    Edit /etc/ipsec.secrets

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    # This file holds shared secrets or RSA private keys for authentication.
    # RSA private key for this host, authenticating it to any other host
    # which knows the public part.
     
    : PSK “TypeYourPassPhraseHere”

    Edit /etc/ppp/options.xl2tpd

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    require-mschap-v2
    refuse-mschap
    ms-dns 8.8.8.8
    ms-dns 8.8.4.4
    asyncmap 0
    auth
    crtscts
    idle 1800
    mtu 1410
    mru 1410
    connect-delay 5000
    lock
    hide-password
    local
    #debug
    modem
    name l2tpd
    proxyarp
    lcp-echo-interval 30
    lcp-echo-failure 4

    Edit /etc/xl2tpd/xl2tpd.conf

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    [global]
    ipsec saref = no
    debug tunnel = no
    debug avp = no
    debug network = no
    debug state = no
    access control = no
    rand source = dev
    port = 1701
    auth file = /etc/ppp/chap-secrets
     
    [lns default]
    ip range = 192.168.1.10-192.168.1.20
    local ip = 192.168.1.1
    require authentication = yes
    name = l2tp
    pass peer = yes
    ppp debug = no
    length bit = yes
    refuse pap = yes
    refuse chap = yes
    pppoptfile = /etc/ppp/options.xl2tpd

    And finally add password to the /etc/ppp/chap-secrets file

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    test    l2tpd     TestTest      “*”
     
    service xl2tpd restart
    service ipsec restart

    Everything should work fine!

    Upd. 2022.01

  • lxd and adjusting size of root device

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    kayama

    That’s normal. With LXD 2.9 and the storage pool changes, LXD stopped generating automatic «root» devices for the containers, instead relying on inheritance from the default profile.

    So in LXD < 2.9, every container had a local «root» device which you could then set properties directly on. With those LXD versions, adding a «root» device to your default profile would be entirely ignored as all containers would override it.

    In LXD > 2.9, containers don’t have any devices by default, they instead rely on inheritance. Meaning that if you want to override it, you have to add a new device to the container with the same name so that it overrides the one coming from the profiles.

    «lxc config show NAME» vs ” lxc config show –expanded NAME ” is pretty useful to see how this all works.

    © https://discuss.linuxcontainers.org/u/stgraber