Skip to content

Instantly share code, notes, and snippets.

@alq666
Created June 18, 2012 03:52
Show Gist options
  • Save alq666/2946739 to your computer and use it in GitHub Desktop.
Save alq666/2946739 to your computer and use it in GitHub Desktop.
xfs-freeze + ebs snapshots
import boto
import logging
import os
import time
import subprocess
import sys
import urllib2
logger = logging.getLogger("pgbackup")
logger.addHandler(level=logging.INFO, logging.handlers.SysLogHandler(facility=logging.handlers.SysLogHandler.LOG_LOCAL0))
def who_am_i():
"""Return one's instance id"""
return urllib2.urlopen('http://169.254.169.254/latest/meta-data/instance-id', timeout=1).read().strip()
def list_ebs(conn, blacklist=["/dev/sda1"]):
"""Get all ebs volumes for oneself
@return [(device, ebs-id), ...]
"""
r = conn.get_all_instances([who_am_i()])[0]
assert len(r.instances) == 1, r.instances
i = r.instances[0]
return [(device, volume) for device, volume in i.block_device_mapping.items() if device not in blacklist]
def snap_ebs(device, volume, conn):
return conn.create_snapshot(volume.volume_id, device)
def freeze(mnt):
logger.info("Calling xfs_freeze -f")
return subprocess.call(["sudo", "xfs_freeze", "-f", mnt]) == 0
def thaw(mnt):
logger.info("Calling xfs_freeze -u")
return subprocess.call(["sudo", "xfs_freeze", "-u", mnt]) == 0
def main():
assert os.path.isdir(sys.argv[1]), "Usage: pgsnap.py xfs_mount_point"
conn = boto.connect_ec2(os.environ["AWS_ACCESS_KEY_ID"], os.environ["AWS_SECRET_KEY_ID"])
vols = list_ebs(conn)
frozen = False
start = time.time()
try:
frozen = freeze(sys.argv[1])
assert frozen, "xfs_freeze failed"
snaps = [snap_ebs(device, volume, conn) for device, volume in vols]
logger.info("Snapshots: {0}".format(snaps))
finally:
if frozen:
thaw(sys.argv[1])
logger.info("XFS was frozen for {0}".format(time.time() - start))
if __name__ == '__main__':
main()
@hughdbrown
Copy link

Style note: change this

def main():
    assert os.path.isdir(sys.argv[1]), "Usage: pgsnap.py xfs_mount_point"
    ...
    try:
        frozen = freeze(sys.argv[1])
        ...
    finally:
        if frozen:
            thaw(sys.argv[1])
            logger.info("XFS was frozen for {0}".format(time.time() - start))

to this:

def main(xfs_mount_point):
    assert os.path.isdir(xfs_mount_point), "Usage: pgsnap.py xfs_mount_point"
    ...
    try:
        frozen = freeze(xfs_mount_point)
        ...
    finally:
        if frozen:
            thaw(xfs_mount_point)
            logger.info("XFS was frozen for {0}".format(time.time() - start))

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment