diff --git a/til.md b/til.md
index dbefec1..593cbfb 100644
--- a/til.md
+++ b/til.md
@@ -5,26 +5,26 @@
Write code like it's synchrone
```javascript
-let get = async (URL) => {
- const retval = await fetch(URL)
- if (retval.ok) {
- this.playlists = await retval.json()
- } else {
- console.error("doh! network error")
- }
-}
-get()
+let get = async URL => {
+ const retval = await fetch(URL);
+ if (retval.ok) {
+ this.playlists = await retval.json();
+ } else {
+ console.error("doh! network error");
+ }
+};
+get();
```
Or use promise chaining
```javascript
fetch(URL)
- .then(stream => stream.json())
- .then(data => this.playlists = data)
- .catch(error => console.error(error))
+ .then(stream => stream.json())
+ .then(data => (this.playlists = data))
+ .catch(error => console.error(error));
```
-
+
## bash
auto-reply `y` on installations or `fsck` repairs
@@ -40,7 +40,6 @@ network diff
FILE=/tmp/a
diff -ru <(sort -u "$FILE") <(ssh user@host "sort -u $FILE")
-
## ffmpeg
extract audio-only from video file with ID3 tags
@@ -51,15 +50,23 @@ record screen
ffmpeg -f x11grab -s 1366x768 -i :0.0 -r 25 -threads 2 -c:v libx264 -crf 0 -preset ultrafast output.mkv
-
## html
```html
```
@@ -74,33 +81,33 @@ drop all incomming ssh connections
iptables -A INPUT -i eth0 -p tcp --dport 22 -m state --state NEW,ESTABLISHED -j DROP
-
## docker
Delete all containers
- * `docker rm $(docker ps -a -q)`
+- `docker rm $(docker ps -a -q)`
Delete all images
- * `docker rmi $(docker images -q)`
+- `docker rmi $(docker images -q)`
Delete all dangling images
- * `docker rmi $(docker images -f dangling=true -q)`
+- `docker rmi $(docker images -f dangling=true -q)`
Create docker network
- * `docker network create mynet`
+- `docker network create mynet`
clean up
- * `docker system prune`
- * `docker volume rm $(docker volume ls -q --filter dangling=true)`
+- `docker system prune`
+- `docker volume rm $(docker volume ls -q --filter dangling=true)`
run two docker `img` container with different names `foo` and `bar` and the can reach each other with domain name `foo` and `bar`
- * `docker run --name foo --net mynet img`
- * `docker run --name bar --net mynet img`
+
+- `docker run --name foo --net mynet img`
+- `docker run --name bar --net mynet img`
copy files from an image to `/tmp/some.file`
@@ -127,7 +134,7 @@ create a patch from a modified file
apply a diff patch
git apply this.patch
-
+
checkout a pull request
add `fetch = +refs/pull/*/head:refs/remotes/origin/pr/*` to `.git/config` under the `[remote "origin"]` section.
@@ -150,19 +157,18 @@ for rom converting
community/ecm-tools 1.03-1 [Installiert]
Error Code Modeler
-
`ecm2bin rom.img.ecm`
# ufw
list all rules
- * `ufw status`
+- `ufw status`
disable/enable firewall
- * `ufw enable`
- * `ufw disable`
+- `ufw enable`
+- `ufw disable`
# systemd
@@ -215,7 +221,7 @@ http {
listen 80;
server_name 127.0.0.1;
-
+
location / {
proxy_redirect off;
proxy_set_header Host $host;
@@ -223,16 +229,16 @@ http {
proxy_set_header Authorization "Basic ZW5lcmdpY29zOmVuZXJnaWNvcw==";
set $cors "1";
-
+
if ($request_method = 'OPTIONS') {
set $cors "${cors}o";
}
-
+
if ($cors = "1") {
more_set_headers 'Access-Control-Allow-Origin: $http_origin';
more_set_headers 'Access-Control-Allow-Credentials: true';
}
-
+
if ($cors = "1o") {
more_set_headers 'Access-Control-Allow-Origin: $http_origin';
more_set_headers 'Access-Control-Allow-Methods: GET, POST, OPTIONS, PUT, DELETE';
@@ -242,7 +248,7 @@ http {
add_header Content-Type text/plain;
return 204;
}
-
+
proxy_pass https://some.url;
}
}
@@ -291,10 +297,15 @@ http {
insert on duplicated for MariaDB/MySQL
```javascript
-async function insert_on_duplicated(table, data){
- let insert = knex(table).insert(data).toString();
- let update = knex(table).update(data).toString().replace(/^update .* set /i, '');
- return await knex.raw(`${insert} on duplicate key update ${update}`);
+async function insert_on_duplicated(table, data) {
+ let insert = knex(table)
+ .insert(data)
+ .toString();
+ let update = knex(table)
+ .update(data)
+ .toString()
+ .replace(/^update .* set /i, "");
+ return await knex.raw(`${insert} on duplicate key update ${update}`);
}
```
@@ -302,7 +313,7 @@ async function insert_on_duplicated(table, data){
list secrets
- * `kubectl -n kube-system get secret`
+- `kubectl -n kube-system get secret`
https://blog.alexellis.io/kubernetes-in-10-minutes/
@@ -324,13 +335,14 @@ place key and sected into `.aws/credentials`
aws_access_key_id = ...
aws_secret_access_key = ...
```
+
and do
- ./goofys --endpoint ams3.digitaloceanspaces.com melmac /home/ec2-user/t/
+./goofys --endpoint ams3.digitaloceanspaces.com melmac /home/ec2-user/t/
# python
-Python json dump with datetime. every time `JSON` doesn't know how to convert a value, it calls
+Python json dump with datetime. every time `JSON` doesn't know how to convert a value, it calls
the `default()` function.
```
@@ -342,45 +354,44 @@ print(json.dumps(my_py_dict_var, default = dtconverter))
```
-
## ML
->> Neural networks are universal approximators - meaning that for any function F and error E, there exists some neural network (needing only a single hidden layer)
-that can approximate F with error less than E.
+> > Neural networks are universal approximators - meaning that for any function F and error E, there exists some neural network (needing only a single hidden layer)
+> > that can approximate F with error less than E.
-* https://en.wikipedia.org/wiki/Artificial_neural_network#Theoretical_properties
-* https://en.wikipedia.org/wiki/Multilayer_perceptron
+- https://en.wikipedia.org/wiki/Artificial_neural_network#Theoretical_properties
+- https://en.wikipedia.org/wiki/Multilayer_perceptron
->> Normalisation is required so that all the inputs are at a comparable range.
+> > Normalisation is required so that all the inputs are at a comparable range.
-With two inputs (x1 and x2), where x1 values are from range 0 to 0.5 and x2 values are from range to 0 to 1000. When x1 is changing by 0.5, the change is 100%, and a
+With two inputs (x1 and x2), where x1 values are from range 0 to 0.5 and x2 values are from range to 0 to 1000. When x1 is changing by 0.5, the change is 100%, and a
change of x2 by 0.5 is only 0.05%.
## puppet
-* list all nodes
+- list all nodes
- puppet cert list --all
+ puppet cert list --all
-* remove a node
+- remove a node
- puppet cert clean
+ puppet cert clean
-* add / accept a node
+- add / accept a node
- puppet cert sign
+ puppet cert sign
# MySQL / MariaDB
dump a live system without blocking
-* for MyISAM
-`nice -n 19 ionice -c2 -n 7 mysqldump --lock-tables=false > dump.sql`
+- for MyISAM
+ `nice -n 19 ionice -c2 -n 7 mysqldump --lock-tables=false > dump.sql`
-* for InnoDB
-`nice -n 19 ionice -c2 -n 7 mysqldump --single-transaction=TRUE > dump.sql`
+- for InnoDB
+ `nice -n 19 ionice -c2 -n 7 mysqldump --single-transaction=TRUE > dump.sql`
-* allow user to create databases with prefix
+- allow user to create databases with prefix
```
GRANT ALL PRIVILEGES ON `dev\_%` . * TO 'dev'@'%';`
@@ -400,7 +411,7 @@ pkg_add bash nano
```
modload lua
luactl create mycpu
-luactl load mycpu ./cpu.lua
+luactl load mycpu ./cpu.lua
```
print to `/var/log/messages` using systm module
@@ -438,8 +449,6 @@ decrypt message with private
openssl rsautl -decrypt -inkey ~/.ssh/my.key -in encrypted_message
-
-
# nextcloud
call `cron.php` from nextcloud which is running in a docker container
@@ -452,7 +461,6 @@ mount with `davfs2`
`sudo mount -t davfs https://nextcloud/remote.php/webdav /mount/point`
-
# xfs
increase filesystem
@@ -462,30 +470,28 @@ increase filesystem
# yubikey
In general you got
- * 2 Slots
- * 32 oath credentials storage
+_ 2 Slots
+_ 32 oath credentials storage
#### oath-hotp 2nd slot for ssh auth
-
1. generate secret
- `dd if=/dev/random bs=1k count=1 | sha1sum`
+ `dd if=/dev/random bs=1k count=1 | sha1sum`
2. flash yubi key slot 2 with generated secret
- `ykpersonalize -2 -o oath-hotp -o oath-hotp8 -o append-cr -a `
+ `ykpersonalize -2 -o oath-hotp -o oath-hotp8 -o append-cr -a `
-#### oath totp for aws
-
-* set
- `ykman oath add -t aws-username `
-* get
- `ykman oath code bergholm -s`
-* list
- `ykman oath list`
+#### oath totp for aws
+- set
+ `ykman oath add -t aws-username `
+- get
+ `ykman oath code bergholm -s`
+- list
+ `ykman oath list`
# ansible
-run tests in docker container
+run tests in docker container
`bin/ansible-test units -v --python 3.7 --docker default`
@@ -499,4 +505,22 @@ variables with an `admin-` prefix are ADMIN variables, and you should use these
UPDATE global_variables SET variable_value='admin:N3wP4ssw3rd!' WHERE variable_name='admin-admin_credentials';
SAVE MYSQL VARIABLES TO DISK;
LOAD MYSQL VARIABLES TO RUNTIME;
-```
\ No newline at end of file
+```
+
+# btrfs
+
+on small devices
+
+`sudo mkfs.btrfs --mixed -f /dev/nvme1n1`
+
+mount with zstd compression
+
+```yaml
+- name: mount with zstd compression
+ mount:
+ path: /mnt/
+ src: /dev/nvme1n1
+ fstype: btrfs
+ opts: compress=zstd,discard,nofail,defaults
+ state: present
+```