IT notes

To enable paste in chrome, open the console and enter: var allowPaste = function(e){ e.stopImmediatePropagation(); return true; }; document.addEventListener('paste', allowPaste, true); …

To load kernel modules after local disks are mounted add this to /etc/rc.conf: kld_list="fuse" in this case module fuse will be loaded …

To get an overview of the system: # sysctl -a | egrep -i 'hw.machine|hw.model|hw.ncpu' hw.machine: amd64 hw.model: Intel(R) Xeon(R) Silver 4110 CPU @ 2.10GHz hw.ncpu: 16 hw.machine_arch: amd64 …

Create a small distributed file system using 2 servers one acting as a mater/chunkserver and other only as a chunkserver. Install the required packages: pkg install moosefs3-cgi moosefs3-cgiserv moosefs3-chunkserver moosefs3-client For the master just add: pkg install moosefs3-master In all the servers add to your /etc/hosts and entry for the mfsmaster: X.X.X.X mfsmaster Before starting the master, crate the file /var/mfs/metadata.mfs with: MFSM NEW Create a pool to share: …

If when trying to install FreeBSD using bsdinstall you get: "Error while fetching file:///usr/freebsd-dist/MANIFEST" - no such file or directory Try to: [email protected]:~ # mkdir -p /usr/freebsd-dist/ [email protected]:~ # touch /usr/freebsd-dist/MANIFEST And then start again …

To send a quit signal to the process: ctrl-\ # (backslash) This will send a SIGQUIT …

To find the python site-packages paths: $ python -m site …

Unbound using DNS over TCP: server: private-domain: "plex.direct" forward-zone: name: "." forward-ssl-upstream: yes forward-addr: [email protected] forward-addr: [email protected] forward-addr: [email protected] forward-addr: [email protected] forward-addr: 2606:4700:4700::[email protected] forward-addr: 2606:4700:4700::[email protected] forward-addr: 2620:fe::[email protected]; forward-addr: 2620:fe::[email protected]; To test do: # unbound-control -c /var/unbound/unbound.conf lookup . It should return something like: The following name servers are used for lookup of . forwarding request: Delegation with 0 names, of which 0 can be examined to query further addresses. …

SSH Canonicalization CanonicalDomains example.com example.net example.org # CanonicalizeFallbackLocal no CanonicalizeHostname yes Host *.example.com IdentityFile ~/.ssh/exampleCOM User foo Host *.example.net IdentityFile ~/.ssh/exampleNET User foo Host *.example.org User foo IdentityFile ~/.ssh/exampleORG more info: https://dotfiles.tnetconsulting.net/articles/2016/0109/ssh-canonicalization.html …

How to connect using serial (usb/com RJ45) port on macOS: $ sudo cu -s 115200 -l /dev/tty.usbserial-DN04FSAL To bail out when you’re done, type ~. as you would with SSH. Boot example: After installing (zfs on root): The toy: …

To upload all packages to packagecloud: package_cloud push immortal/immortal/el/7 immortal_0.19.0_*.rpm --skip-errors for .deb 386 needs to be i386 …

Gzip all files within a directory: gzip -r ./ or find . -type f ! -name '*.gz' -exec gzip "{}" \; …

Disabling blinking blue led: echo none > /sys/class/leds/blue:heartbeat/trigger To make the change permanent add the line to /etc/rc.local …

exec is a functionality of an operating system that runs an executable file in the context of an already existing process, replacing the previous executable. https://en.wikipedia.org/wiki/Exec_(system_call) exec replaces the current program in the current process, without forking a new process. Examples to use: exec csh This will just replace the existing shell with csh and only need to type exit once Within a script to startup python scripts, for example: …

The sockstat command list open Internet or UNIX domain sockets. List open tcp in ipv4: # sockstat -4l Show connectd sockets in port 443 and tcp: # sockstat -P tcp -p 443 -c List unix sockets: # sockstat -u …

To send a command to all the servers within a playbook: $ ansible all -a "service chronyd restart" -u devops --become What’s an ad-hoc command? An ad-hoc command is something that you might type in to do something really quick, but don’t want to save for later. http://docs.ansible.com/ansible/latest/user_guide/intro_adhoc.html …

Update Freebsd using freebsd-update: Set in /etc/rc.conf: kern_securelevel_enable="NO" kern_securelevel="0" reboot and then: # freebsd-update upgrade -r 10.4-RELEASE # freebsd-update install # reboot # freebsd-update install Repeate then to upgrade to 11.1 freebsd-update upgrade -r 11.1-RELEASE Only security patches: # freebsd-update fetch # freebsd-update install To update the packages: # pkg-static upgrade -f # freebsd-update install A forced upgrade of all installed packages will replace the packages with fresh versions from the repository even if the version number has not increased. …

Basic influxdb queries, setup. You can use influx (the influxdb shell) or use the http API on port :8086 Create and apply retention policy to a database: warning this may remove/purge existing data CREATE RETENTION POLICY "30_days" ON collectd DURATION 30d REPLICATION 1 default notice the ending default that means to apply the created policy Show retention policies: > show retention policies name duration shardGroupDuration replicaN default ---- -------- ------------------ -------- ------- autogen 0s 168h0m0s 1 false 30_days 720h0m0s 24h0m0s 1 true Show databases contents (measurements): …

To enable WoL (Wake-on-LAN) on macOS: $ sudo pmset womp 1 Then check the settings: $ pmset -g System-wide power settings: Currently in use: standbydelay 10800 standby 1 womp 1 halfdim 1 hibernatefile /var/vm/sleepimage powernap 1 gpuswitch 2 networkoversleep 0 disksleep 10 sleep 1 (sleep prevented by coreaudiod, coreaudiod, iTunes) autopoweroffdelay 28800 hibernatemode 3 autopoweroff 1 ttyskeepawake 1 displaysleep 10 tcpkeepalive 1 acwake 0 lidwake 1 …

If your domain becomes blocked you “could use” another one to bypass the block: curl -s -H "Host: your-blocked-domain" -H "Connection: close" "https://new-tld/your/path" Both domains must be hosted within the same CDN, example: curl -s -H "Host: images-na.ssl-images-amazon.com" -H "Connection: close" "https://cdn.atlassian.com/images/I/01rgQ3jqo7L.css" More info: https://www.optiv.com/blog/escape-and-evasion-egressing-restricted-networks https://www.peew.pw/blog/2018/2/22/how-i-identified-93k-domain-frontable-cloudfront-domains …