Being a Tale of Databases, Binary Logs, WAL Files, and the Redemption of Ebenezer Scrooge, DBA
Part the First — In Which We Meet Ebenezer Scrooge, Database Administrator Extraordinary
It was a cold, dark, and CPU-bound night. The wind blew fierce across the datacenter racks, and the disks did rattle in their trays like bones. Ebenezer Scrooge, Senior Database Administrator (Level III, self-certified), sat hunched o’er his terminal, lit only by the ghostly glow of Vim. He was a man of bytes and bits, parsimonious with his time, and proud — oh, so proud! — of never once taking a backup.
He refused to invest in proper backup solutions, believing that “databases are meant to be live, not backed up.” His servers were old, his storage was limited, and his disaster recovery plans were non-existent.
“Backups?” quoth Scrooge. “Bah! WAL-humbug! Real men make no backups, and if the data be lost, ‘tis but the user’s fault for querying unwise.”
His junior assistant, young Cratchit — a timid lad who kept his .pgpass neat, his /etc/mysql/my.cnf curated like scripture, his pg_basebackup cronjob tidy, and his xtrabackup schedules tidier still — dared whisper with the caution of a man who had seen replication break in the night:
“Sir… should we not test the Point-in-Time Recovery procedures — both PostgreSQL and MySQL — afore we trust them in production? For WALs and binlogs alike must prove their worth in the hour of calamity.”
Scrooge scowled, turning upon him the full radiance of a man certain of his own immortality.
“PITR? BINLOG REPLAY? I have no time for such phantasms! I tune autovacuum! I optimize InnoDB buffer pools! I am master of checkpoints and vacuum freeze, of redo logs and doublewrite buffers! My databases are eternal!”
He rose, pacing the room with growing arrogance.
“Why should I test restoring a PostgreSQL cluster when my WAL archiver never fails? Why should I practice restoring MySQL when my GTIDs flow pure and my replicas lag not? Backups are the indulgence of cowards — but I am Scrooge! I have uptime! I have replicas! I have faith!”
Cratchit swallowed hard, for he had heard such boasts before from DBAs now long vanished from the profession.
And so saying, Scrooge closed his laptop, muttering curses against backup scripts and S3 buckets, and went home to his lonely flat, where even systemctl feared to run.
Part the Second — The Ghost of Backups Past
That night, as Scrooge lay in bed surrounded by cold, blinking router lights, there came a sound — clink-clank-clunk, like the weary drive heads seeking across ancient HDD platters, hunting for sectors long forgotten. A spectral figure emerged, its form woven of compressed database parts and binary log archives, trailing a long chain of WAL files that scraped across the floor like metal on stone.
“Who art thou?” cried Scrooge, clutching his pillow like a frightened sysadmin clutching an unmounted volume.
“I am the Ghost of Backups Past,” said the figure, “and these are the chains I made when thou didst disable cron. Behold!”
The room shimmered, and they found themselves in the server room of yore – humming, orderly, and bathed in the pale glow of console monitors. There, a younger Scrooge bent over his keyboard with cautious devotion, tending to his engines as a shepherd tends his flock.
On one terminal, he issued:
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pg_basebackup -D /mnt/backup -Ft -z |
The output shone bright and green, on another screen, without hesitation, he invoked:
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xtrabackup --backup --target-dir=/backups/full_2025-12-24 |
The logs rolled by, steady and reassuring, the backup chain whole and sound.
“Behold, Ebenezer,” said the spirit. “In those days thou didst honor both thy databases alike. Thou didst backup every file, test every restore, and trust neither WAL nor binlog until they proved themselves upon a staging host. Thy users slept peacefully, guarded by the redundancy of thy diligence.”
But the vision dimmed.
The younger Scrooge straightened, pride creeping across his face like shadow over a failing disk.
“Backups slow the system,” he declared. “Hot backups are for the faint of heart. Replication alone shall be my shield.”
At once, the WALs withered, the base backup collapsed into dust, the binlog chain broke like a brittle link, and metadata evaporated into the stale air of the abandoned server room.
The spirit’s voice trembled.
“Mark my words, Ebenezer: when the foundation is cast aside, the WALs of the present find no place to land, nor the binlogs any moment from which to begin. Replication is not salvation — for corruption replicates faster than truth. Forget this lesson, and all shall be lost.”
As the ghost dissolved into swirling TAR fragments and drifting binary dust, Scrooge heard a fading chorus:
“the harsh cry of rsync failing with exit code 12…”
and beneath it, a whisper as soft as a lost packet on the wire:
“prepare your backups… prepare your backups…”
Part the Third — The Ghost of Logs Present
Scrooge awoke at the stroke of midnight to see a mighty specter clad in the green robes of pg_wal. Around his waist hung a belt of flashing GTIDs, and from his hands streamed an endless scroll of WALs, half bathed in golden MySQL binlogs.
“I am the Ghost of LOGS Present,” he boomed. “Come, Ebenezer! See how thy database yet breathes, thanks to mine continuous write-ahead redemption!”
They flew through the night to the production host. There, diligent Cratchit tended the WAL archives and binary logs like a shepherd, ensuring that archive_command returned true, checked the replica lag with care, and that the S3 bucket overflowed not.
“These logs,” said the Ghost, “record every humble INSERT, every noble COMMIT. Without them, no recovery to any point could be done.”
Scrooge gazed in awe as the spirit waved his arm. The GTIDs and LSNs flowed like a river of time, and the Ghost did cry:
“See, Ebenezer! Point in Time Recovery — the miracle of moments restored!”
He showed him how restore_command and recovery_target_time might summon a fallen PostgreSQL cluster from the ashes, restoring it to the very heartbeat before disaster struck; and how, in the realm of MySQL, the careful invocation of mysqlbinlog, guided by one’s chosen stop-datetime, could weave binlog events anew, re-creating the world as it was before calamity descended.
Scrooge trembled, whispering:
“’Tis sorcery… nay, not sorcery at all — ’tis but PostgreSQL and MySQL, each wielding its own sacred logs to turn back the tide of ruin.”
But as he looked closer, the WALs began to falter. The S3 bucket dried up. The binary logs ceased to appear. The ghost’s robe dimmed.
“My time grows short,” said the spirit. “Without backups, my work is naught. When the base backup is gone, I have no origin to replay upon. Without logs, I cannot reconstruct thy transactions. Your Present is doomed if the Past is lost.”
And the Ghost of LOGS Present faded, leaving only a faint echo:
“Keep thine archives safe, and thy database shall live again.”
Part the Fourth — The Ghost of Backups Yet to Come
The clock struck one, and all the blinking LEDs in Scrooge’s flat fell dark. A silence heavier than fsync delay filled the air. A shadow fell upon the room. The temperature dropped, and the blinking lights of the routers dimmed to a ghostly flicker. From the darkness emerged a towering figure, its form shrouded in mystery, clad in tattered remnants of corrupted data files and broken replication chains.
“Art thou… the Ghost of Backups Yet to Come?” quavered Scrooge.
The figure nodded solemnly, its eyes glowing with an eerie light. In one hand, it held a shattered PostgreSQL cluster, its files corrupted beyond repair. In the other, a ruined MySQL instance, its InnoDB tablespaces mangled and unreadable.
“Good heavens!” cried Scrooge. “Where are the initial backups? Where are the archived WALs? Where are the binary logs?”
The spirit pointed to a crumbling drive in the corner, its SMART status failed, its RAID array degraded, its S3 credentials expired three years hence.
“Surely,” pleaded Scrooge, “I can restore from my replicas!”
The phantom turned, and before them lay a smoking ruin of replication errors:
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Last_SQL_Errno: 1236 Last_SQL_Error: Replica has failed to open the relay log file |
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2025-12-25 00:00:00.000 UTC [28] FATAL: could not receive data from WAL stream: ERROR: requested WAL segment 00000001000000000000000A has already been removed |
The ghost pointed to a lonely email from management:
“We regret to inform you that the production databases have been lost. We hope the memes were worth it.”
The developers wept. The CEO paced the hall. The CFO fainted upon hearing that no snapshot, no backup, no replica could be restored.
Scrooge fell to his knees, clutching at the hem of the phantom’s robe.
“Spirit! I see it now! A database without backups is but a castle built on volatile storage! I shall change! I shall back up hourly, test weekly, and monitor the archiver! I will use xtrabackup and pgBackRest and verify every restore!”
At this, the phantom’s hood fell back — and beneath it, Scrooge saw not a skull, but an empty directory: /mnt/backup. He screamed — and awoke.
Part the Fifth — In Which Scrooge is Restored
Morning sunlight streamed across his desk, reflecting off his coffee mug that read “Real DBAs Make No Backups”. With trembling hands, Scrooge seized it and cast it into the bin.
“No more!” he cried. “This day I shall initiate a global backup strategy, and verily shall I archive both binlogs and WALs with discipline!”
He dashed to his workstation, his fingers flying across the keyboard like angels upon the harp of recovery. Then he edited configuration files with trembling reverence.
And he added cronjobs, aye, blessed cronjobs, that the ghosts of Backups Past and WALs Present might smile upon him forevermore.
That evening, Scrooge did summon young Cratchit and spake thus:
“My boy, from this day forth, thou shalt verify every backup, thou shalt test the PITR procedures quarterly, and thou shalt keep secondaries in warm standby. Here — take this pgBackRest configuration, and mind thou set the retention policy!”
Cratchit wept for joy.
And the users rejoiced, for their queries no longer feared corruption, nor downtime, nor the wrath of lost log segments. The databases lived again, restored to a point in time of righteousness and consistency.
And it was said from that day forward, in every data center and cloud region, that there was no DBA more vigilant, nor database more secure, than old Ebenezer Scrooge, who had learned at last the gospel of Database Point In Time Recovery.
He spoke often to the next generation:
“Children, replication is not a backup. Backups are a backup. And a tested restore is the only backup that truly exists.”
And it was said that no cluster under Scrooge was ever lost again, for both WAL and binlog smiled upon him.
About the Author
Pep PlaPep has been working with databases all his life. Born in a small village by the Mediterranean, he currently lives in Barcelona. He loves tech, traveling, good food, music and, all things NASA. He hates talking about himself in the third person and has a particular sense of humor. Happily married, he is the father of three boys and three cats.
