Merge branch 'master' of gitea.hptrow.me:pt/notes

badges.md

@@ -0,0 +1,3 @@
+shields.io
+
+[![License: GPL v3](https://img.shields.io/badge/License-GPL%20v3-blue.svg)](https://www.gnu.org/licenses/gpl-3.0)

bash.md

@@ -1,3 +1,5 @@
+https://wiki.bash-hackers.org/
+
 
 Update PostgreSQL
 ------------------------------------------------------------------------------------------------------------

pgbdager.md

@@ -1,3 +1,3 @@
 creates a file `out.html` by default
 
-    sudo pgbadger --prefix '%t [%p]: [%l-1] user=%u,db=%d,app=%a,client=%h,remote=%r ' //var/log/postgresql/postgresql-2020-02*
+    sudo pgbadger --prefix '%t [%p]: [%l-1] user=%u,db=%d,app=%a,client=%h,remote=%r ' //var/log/postgresql/postgresql-2020-02*

postgres/out_of_memory.md

@@ -0,0 +1,12 @@
+logs from trying to start with not enough memory:
+```
+207716 2020-02-11 11:33:02 EST [2969]: [1-1] user=,db=,app=,client=,remote=LOG:  starting PostgreSQL 12.1 (Ubuntu 12.1-1.pgdg18.04+1) on x86_64-pc-linux-gnu, compiled by gcc (Ubuntu 7.4.0-1ubuntu1~18.04.1) 7.4.0, 64-bit
+207717 2020-02-11 11:33:02 EST [2969]: [2-1] user=,db=,app=,client=,remote=LOG:  listening on IPv4 address "0.0.0.0", port 5030
+207718 2020-02-11 11:33:02 EST [2969]: [3-1] user=,db=,app=,client=,remote=LOG:  listening on IPv6 address "::", port 5030
+207719 2020-02-11 11:33:04 EST [2969]: [4-1] user=,db=,app=,client=,remote=LOG:  listening on Unix socket "/var/run/postgresql/.s.PGSQL.5030"
+207720 2020-02-11 11:33:06 EST [2969]: [5-1] user=,db=,app=,client=,remote=FATAL:  could not map anonymous shared memory: Cannot allocate memory
+207721 2020-02-11 11:33:06 EST [2969]: [6-1] user=,db=,app=,client=,remote=HINT:  This error usually means that PostgreSQL's request for a shared memory segment exceeded available memory, swap space, or huge pages. To reduce the request size (currently 4423614464 bytes       ), reduce PostgreSQL's shared memory usage, perhaps by reducing shared_buffers or max_connections.
+207722 2020-02-11 11:33:06 EST [2969]: [7-1] user=,db=,app=,client=,remote=LOG:  database system is shut down
+207723 pg_ctl: could not start server
+207724 Examine the log output.
+```

ubuntu/networking.md

@@ -4,7 +4,19 @@ sudo nmap -T Aggressive -A -v 127.0.0.1 -p 1-10000
 
 sudo netstat --tcp --udp --listening --program
 
+lists programs with port numbers: `sudo netstat -tup`
+
 sudo lsof +M -i4 -i6
 
 let's encrypt certbot instructions for apache:
-https://certbot.eff.org/lets-encrypt/ubuntubionic-apache
+https://certbot.eff.org/lets-encrypt/ubuntubionic-apache
+
+
+ip setup:
+https://help.ubuntu.com/lts/serverguide/network-configuration.html
+
+
+## network interfaces
+`ip link` lists all interfaces
+multipass setup some dummy interfaces and left them there.
+to delete did `ip link delete mpqemubr0-dummy`

vagrant.md

@@ -0,0 +1,17 @@
+vagrant has releases at https://releases.hashicorp.com/vagrant/2.2.7/
+
+curl -O https://releases.hashicorp.com/vagrant/2.2.7/vagrant_2.2.7_x86_64.deb
+
+then `sudo apt install ./file.deb`
+
+although if you go to the downloads page, it looks like it gives you a zip of the binary if you want to drop that somewhere.
+
+set the vagrant file to uncomment the public network option and specify some additional info
+
+vagrant init ubuntu/bionic64
+
+`config.vm.network "public_network", bridge: "eno1", ip: "192.168.1.115"`
+
+vagrant up
+vagrant ssh
+vagrant halt

virtualbox.md

@@ -0,0 +1,16 @@
+install from Oracles repo
+
+https://itsfoss.com/install-virtualbox-ubuntu/
+
+
+add key for repo 
+
+    wget -q https://www.virtualbox.org/download/oracle_vbox_2016.asc -O- | sudo apt-key add -
+
+add virtualbox to list of repositories
+
+    sudo add-apt-repository "deb [arch=amd64] http://download.virtualbox.org/virtualbox/debian $(lsb_release -cs) contrib"
+
+`apt-get install virtualbox-6.1`
+
+vboxmanage is the cli program

webmin.md

@@ -0,0 +1,2 @@
+install on Ubunut
+https://doxfer.webmin.com/Webmin/Installation#apt_.28Debian.2FUbuntu.2FMint.29