Attachment 10746 Details for Bug 53221

migrate-samldb-from-tdb-to-mdb

migrate-samldb-from-tdb-to-mdb (text/x-python), 5.53 KB, created by Arvid Requate on 2021-06-09 23:29 CEST

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Creator: Arvid Requate

Created: 2021-06-09 23:29 CEST

Size: 5.53 KB

patch

obsolete

>#!/usr/bin/python
>import argparse
>from contextlib import contextmanager
>from datetime import datetime
>import ldb
>import os
>from samba import Ldb
>from samba.auth import system_session
>from samba.param import LoadParm
>import shutil
>import subprocess
>import sys
>import tdb
>import time
>
>
>def install_python_lmdb():
>    from univention.config_registry import ConfigRegistry, handler_set
>    ucr = ConfigRegistry()
>    ucr.load()
>    if not ucr.is_true("repository/online/unmaintained"):
>        handler_set(["repository/online/unmaintained=yes"])
>        subprocess.call(("univention-install", "python-lmdb"))
>
>
>try:
>    import lmdb
>except ImportError:
>    install_python_lmdb()
>    import lmdb
>
># Default the mdb file size for the individual partitions to 8GB
>DEFAULT_BACKEND_SIZE = 8 * 1024**3
>
>def migrate_sam_ldb_backends_from_tdb_to_mdb(ldb_tdb_backend_dir, ldb_mdb_backend_dir):
>    print("PROCESS: Migrating sam.ldb.d backend files from TDB to MDB")
>    ldb_tdb_backend_files = [fn for fn in os.listdir(ldb_tdb_backend_dir) if fn.endswith(".ldb")]
>    for fn in ldb_tdb_backend_files:
>        t = tdb.Tdb(os.path.join(ldb_tdb_backend_dir, fn))
>        mdb_env = lmdb.open(os.path.join(ldb_mdb_backend_dir, fn), map_size=DEFAULT_BACKEND_SIZE, subdir=False)
>        os.chmod(mdb_env.path(), 0o600)
>
>        with mdb_env.begin(write=True) as txn:
>            for i in t:
>                txn.put(i, t[i])
>    print("PROCESS: Migration of sam.ldb.d backend files done")
>
>
>@contextmanager
>def sam_ldb_backends_from_tdb_to_mdb(lp):
>    print("PROCESS: Creating new sam.ldb.d directory for Migration")
>    sam_backend_dir = lp.private_path("sam.ldb.d")
>    sam_tdb_backend_dir = lp.private_path("sam.ldb.tdb.d")
>    sam_ldb = lp.private_path("sam.ldb")
>    sam_ldb_bak = lp.private_path("sam.ldb.tdb")
>
>    try:
>        os.rename(sam_backend_dir, sam_tdb_backend_dir)
>    except OSError:
>        print("ERROR: An exception occurred, aborting migration")
>        raise
>
>    os.mkdir(sam_backend_dir)
>    os.chmod(sam_backend_dir, 0o700)
>
>    shutil.copy(sam_ldb, sam_ldb_bak)
>    os.chmod(sam_ldb_bak, 0o600)
>
>    migrate_sam_ldb_backends_from_tdb_to_mdb(sam_tdb_backend_dir, sam_backend_dir)
>
>    try:
>        yield
>    except Exception:
>        print("ERROR: An exception occurred, reverting sam.ldb.d to original state")
>        shutil.rmtree(sam_backend_dir)
>        os.rename(sam_tdb_backend_dir, sam_backend_dir)
>        os.unlink(sam_ldb)
>        os.rename(sam_ldb_bak, sam_ldb)
>        raise
>
>    print("PROCESS: Moving metadata file to new sam.ldb.d directory")
>    os.rename(os.path.join(sam_tdb_backend_dir, "metadata.tdb"), os.path.join(sam_backend_dir, "metadata.tdb"))
>
>
>def open_samdb_raw(lp):
>    # Use options=["modules:"] to keep the attached LDB modules from loading
>    samdb_path = lp.private_path("sam.ldb")
>    return Ldb(url=samdb_path, session_info=system_session(),
>                            lp=lp, options=["modules:"])
>
>
>def activate_mdb(lp):
>    print("PROCESS: Switching sam.ldb from TDB to MDB")
>    samdb = open_samdb_raw(lp)
>
>    samdb.transaction_start()
>    try:
>        delta = ldb.Message()
>        delta.dn = ldb.Dn(samdb, "@PARTITION")
>        delta["backendStore"] = \
>           ldb.MessageElement("mdb",
>                           ldb.FLAG_MOD_REPLACE,
>                           "backendStore")
>        samdb.modify(delta)
>
>        delta = ldb.Message()
>        delta.dn = ldb.Dn(samdb, "@SAMBA_DSDB")
>        delta["requiredFeatures"] = \
>           ldb.MessageElement("lmdbLevelOne",
>                           ldb.FLAG_MOD_ADD,
>                           "requiredFeatures")
>        samdb.modify(delta)
>    except ldb.LdbError:
>        samdb.transaction_cancel()
>        print("PROCESS: Switching sam.ldb from TDB to MDB failed")
>        raise
>    else:
>        samdb.transaction_commit()
>        print("PROCESS: Switching sam.ldb from TDB to MDB successful")
>
>
>@contextmanager
>def stopped_samba_and_s4c():
>    print("PROCESS: Stopping Samba and S4-Connector")
>    subprocess.call(("systemctl", "stop", "univention-s4-connector"))
>    subprocess.call(("/etc/init.d/samba", "stop"))
>
>    try:
>        yield
>    except Exception:
>        raise
>
>    print("PROCESS: Starting Samba and S4-Connector again")
>    subprocess.call(("/etc/init.d/samba", "start"))
>    time.sleep(5)
>    subprocess.call(("systemctl", "start", "univention-s4-connector"))
>
>
>def sam_ldb_is_using_mdb(lp):
>    samdb = open_samdb_raw(lp)
>    res = samdb.search(base="@PARTITION", scope=ldb.SCOPE_BASE, attrs=["backendStore"])
>    return (res and "backendStore" in res[0] and str(res[0]["backendStore"]) == "mdb")
>
>
>if __name__ == "__main__":
>    parser = argparse.ArgumentParser(description="Migrate sam.ldb from TDB to MDB")
>    parser.add_argument("--skip-dbcheck", action='store_true')
>    args = parser.parse_args()
>
>    lp = LoadParm()
>
>    if sam_ldb_is_using_mdb(lp):
>        print("INFO: Nothing to do, sam.ldb is already using MDB")
>        sys.exit(0)
>
>    with stopped_samba_and_s4c():
>        if not args.skip_dbcheck:
>            print("PROCESS: Running pre-migration check of sam.ldb database")
>            if subprocess.call(("samba-tool", "dbcheck", "--cross-ncs")):
>                sys.exit(1)
>
>        t0 = datetime.now()
>
>        with sam_ldb_backends_from_tdb_to_mdb(lp):
>            activate_mdb(lp)
>
>        duration = str(datetime.now() - t0).split('.')[:-1][0]
>        print("INFO: Duration: %s" % duration)
>
>        if not args.skip_dbcheck:
>            print("PROCESS: Running post-migration check of sam.ldb database")
>            if subprocess.call(("samba-tool", "dbcheck", "--cross-ncs")):
>                sys.exit(1)
>

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Attachments on bug 53221: 10745 | 10746