Freebsd Partition EC2 AWS disk

In Amazon web services, we can create an AMI that takes a snapshot of our current instance. However, there are times that we need to create an instance with higher disk space using an AMI having a lower disk space.
Following the instructions from: https://www.freebsd.org/doc/handbook/disks-growing.html
After having creating the instance, and specifying a disk of 30gb, (the AMI was only 10gb) it show’s that the 20GB were free.

# gpart show ada0
=>       0  62914560  ada0  BSD  (30G)
         0        16        - free -  (8.0K)
        16  20971504     1  !0  (10G)
  20971520  41943040        - free -  (20G)

We can expand this root via the following commands:

#sudo gpart resize -i 1 -a 4k -s 29G ada0
ada0a resized

Now we can see that its ready for the partitioned,

# gpart show ada0
=>       0  62914560  ada0  BSD  (30G)
         0        16        - free -  (8.0K)
        16  60817408     1  !0  (29G)
  60817424   2097136        - free -  (1.0G)

Apply the partition using:

# sudo growfs /dev/ada0a
Device is mounted read-write; resizing will result in temporary write suspension for /.
It's strongly recommended to make a backup before growing the file system.
OK to grow filesystem on /dev/ada0a, mounted on /, from 10GB to 29GB? [Yes/No] Yes
super-block backups (for fsck_ffs -b #) at:
 21798272, 23080512, 24362752, 25644992, 26927232, 28209472, 29491712, 30773952, 32056192, 33338432, 34620672, 35902912, 37185152, 38467392, 39749632, 41031872, 42314112, 43596352, 44878592, 46160832, 47443072, 48725312, 50007552, 51289792, 52572032, 53854272, 55136512,
 56418752, 57700992, 58983232, 60265472

Check the partition after

staging% df -h
Filesystem    Size    Used   Avail Capacity  Mounted on
/dev/ada0a     28G    7.0G     19G    27%    /
devfs         1.0K    1.0K      0B   100%    /dev
fdescfs       1.0K    1.0K      0B   100%    /dev/fd

Postgres INHERITS partition table with Flask SQLAlchemy

Sqlachemy

Sqlalchemy version 1.0.0 released a feature to support postgres inheritance. Had a quite a time to implement in a Flask-Sqlalchemy.

 1 from app import db, app, bcrypt, redis
 2 
 3 class GarrisonProperty(db.Model):
 4     __tablename__ = 'garrison_properties'
 5 
 6     id = db.Column(db.Integer(), primary_key=True)
 7     building_id =  db.Column(db.Integer())
 8     level = db.Column(db.Integer())
 9     build_cost = db.Column(db.Integer())
10     build_time = db.Column(db.Integer())
11 
12 class Townhall(db.Model):
13     __tablename__ = "townhall"
14     __table_args__ = (
15     ¦   db.PrimaryKeyConstraint('building_id', 'level'),
16     ¦   {'postgresql_inherits' : 'garrison_properties'}
17     )
18 
19     id = db.Column(db.Integer())
20     building_id =  db.Column(db.Integer())
21     level = db.Column(db.Integer())
22     build_cost = db.Column(db.Integer())
23     build_time = db.Column(db.Integer())
24     unlocks = db.Column(db.Integer())

We wanted something that is simple and doesn't really want to the SQLAlchemy join. By this implementation, it should simplify our database structure.

We had to bring all the attributes from the parent model (GarrisonProperty) into the child just to have the access. The db shouldn't do any duplicates for it.

Source:
https://bitbucket.org/zzzeek/sqlalchemy/issue/2051/support-postgresql-table-options