Table of Contents

Poznamky k KVM virtualizaci a zalohovani

seznam praktickych prikazu 

    virsh list
    virsh edit testing

Escape character is ^]

Takhle se hledaji a instaluji baliky 

    apt search agent | grep guest
    apt install qemu-guest-agent

virsh snapshot-create-as –domain testing try1 –atomic —flags disk-only a quiesce vyvolaju permission error

virsh -c qemu:/system domblklist testing — zoznam .qcow2 virsh -c qemu:/system dumpxml testing > /srv/storage/backup/testing_backup.xml

jak pouzivat aplikace virtualenv -

24.10. 1)https://kashyapc.wordpress.com/2012/09/14/externaland-live-snapshots-with-libvirt/ toto je celkom useful link, ale ako navod to nefunguje kvoli permissions. Je tam aspon vysvetleny rozdiel medzi internal a external snapshot. Domnievam sa, ze nas zaujima external. Internal sa mi uz predtym vlastne podaril. o permissions pre qemu neexistuju ziadne zdroje, ani dokumentacia qemu sa o nicom takom poriadne nezmienuje.

zapamataj si definice: qemu - emulator libvirt - API pre manazovanie roznych VM virsh - cmd interface zalozeny na libvirt

2) snazil som sa skumat moznost qemu-img. https://serverfault.com/questions/692435/qemu-img-snapshot-on-live-vm

pomocou poslednej odpovede tu ide vytvorit kopiu qcow2 suboru. Podla tej odpovede toto + xml s config VM staci na back-up.


25.10
Pri blizsom pohlade sa to javi ako dost nezmysel.
dalsie useful linky:
https://gist.github.com/ringe/334ee88ba5451c8f5732//
http://soliton74.blogspot.com/2013/08/about-kvm-qcow2-live-backup.html
Stu tam cele scripty co robia ten back up . Problem je ten, ze pouziju tie iste prikazy co nam nejde spustit.
chown -R libvirt-qemu:kvm “$BASEPATH” toto vyzera ako zaujimavy napad ale nejde to spustit
potencialne uzitocne: dpkg queries, installs, removes, and maintains Debian software packages and their dependencies
strace vyvola nejaky vypis volania do kernelu


Vim

:%s/search/replace/gc


26.10. Stalo sa ze, storage odmietol reagovat- host is down. Staci umount storage, mount storage a hotovo


Heslo do virsh console testing: ahoj……, login root


Takze. Mal by som si do utorka zapamatat, co mam vlastne robit. Externe snapshoty su po vytvoreni inverzne. T.j. ten backup je povodny a zmeny sa ukladaju do toho snapu. Preto vytvorime kopiju toho povodneho .qcow2 niekam mimo a dalej bezi vm na tom snapshote————–> https://wiki.libvirt.org/page/Live-disk-backup-with-active-blockcommit


30.10. virsh blockcommit jakub-sevcik /vps/jakub-sevcik2018-10-30 –active –verbose –pivot —fungovalo asi tak ako sme dufali. Takze proces je 1. dumpxml 2. create snapshot 3. okopirovat backup 4. blockcommit 5. odmazat snap 6. ??? 7. profit


31.10. import: os, subprocess, stat na vytvorenie executable suboru
(import libvirt)
virsh list:
con = openReadOnly( adresa, k najdeniu v godsview models alebo views )
list = con.ListAllDomains(0)
.name() —————→ testing, jakub-sevcik atd.

New server

echo jmeno >/etc/hostname
hostname jmeno
echo domain starlab.cz >>/etc/resolv.conf
bash
echo frozen > /sys/block/md0/md/sync_action
echo frozen > /sys/block/md1/md/sync_action
echo frozen > /sys/block/md2/md/sync_action
apt update
apt install puppet
puppet agent -t

Add the server to “VHOST class at puppet.starlab.cz” and run the puppet agent -t again.

Add the new server to vSwitch vlans (usualy vlan10, vlan11 and vlan40)

6.11.

Praca s databazou. Problemy: 
1. Duplikatne mena vps cez VHost
2. Cele robit co najviac cez db. Pozmenit mozno nejak ten refresh nech mi fetchne tie potrebne data
3.

Fail2ban

fail2ban-client set sshd unbanip 88.198.64.144

.

20.11. -- SSH v pythone

   from pexpect import pxssh
   s = pxssh.pxssh()
   s.login('h6', 'root')

prikaz linux na vyzkouseni zda je gueatagent na virtual windows nainstalovan: virsh qemu-agent-command testing '{“execute”:“guest-info”}' 

postup na vydanie do produkcie: 
ideal nebyt na django prihlaseny ako root, ale ako vps. Asi je ale problem s pravami na git
bin/actiovate,  git pull
pripadne zmenit vlastnika suborom aby to bol vps
makemigrations/ migrate
./manage.py createsuperuser

to by malo byt technicky vsetko
https://www.layoutit.com/

Storage sizes app - useful linky co sa asi zidu 

https://www.reddit.com/r/django/comments/319u80/how_do_you_setup_django_with_remote_database/
https://www.quora.com/How-does-python-Django-connect-to-a-remote-database
https://stackoverflow.com/questions/6536783/django-getting-data-from-different-database
https://docs.djangoproject.com/en/2.1/ref/contrib/contenttypes/
https://docs.djangoproject.com/en/2.1/topics/db/multi-db/
toto by malo byt riesenie mojho najvacsieho problemu projektu- ako sa dostat do databaz cudzich projektov. Snad
pre vsetky vps
for x in `virsh list | tr -s ' ' | cut -d' ' -f3`; do virsh domblklist $x; done
 
WEBHOSTING PASSWD: Born2runIneptus
 
Formatovanie JSON: 
json pretty print (google)

Fail2ban

fail2ban-client set sshd unbanip 88.198.64.144
supervisorctl restart ...
virsh -c qemu:///system list

Curl requests format

curl –header “Content-Type: application/json” –request POST –data '{ “amount”: “512”, “ico”: null,“dic”: “”,“account_no”: “666”,“bank_no”: “4200”, “invoice_items”: []}' –user uziv:aho…… http://127.0.0.1:8000/api/out_invoice/

curl -X POST -F 'amount=1024' -F 'invoice_items=[]' -F 'note=Curl test-form' -F 'picture_pro_forma=@/srv/fakturace2/fakturace2/invoice_pictures/2019-61667812_5cO24If.pdf' –user uziv:aho…… http://127.0.0.1:8000/api/incoming_invoices/

GET /api/incoming_invoices/?company_id=4bd3f127-9700-46d4-868a-a467e2e34042