The Book of Coming Forth by Reboot · Chapter 4

The Rite of the Opening of the Mouth of the Server

1. 1

   And it came to pass in the House of Gold, which is the build pipeline, that a server was fashioned from the image; and its body was whole, its kernel carved and its packages set in order, and the meter began to run upon it in the very hour of its carving. Yet it was not alive. For it was provisioned, which is to say it stood upon the invoice; and a thing that standeth upon the invoice is not a thing that can serve.

2. 2

   And the priest came unto it, who is no man but a script, cloud-init by name. He is not carried in from without; he is read from the address that is no address, 169.254.169.254, which answereth only the machine that asketh it, saying: Who am I, and what am I to become? And the scroll that is handed down is called user-data, and upon the cloud of Virginia it may not exceed sixteen thousand bytes; for a whole life must be written small.

3. 3

   And the priest took in his hand the adze of sky-iron, and he read in four readings: the first before the network was awake, the second when it woke, the third for the settings, and the fourth for the last things. And in the first reading he gave the server its name and its instance-id, that it might be called in the day of judgment; and he made for it a new seal, a host key that no sibling shareth. For two statues with one seal cannot be told apart, and the stranger who cannot tell them apart will trust the wrong one.

4. 4

   Then he touched the eyes of the server and said: Open, and see. And he grew the root partition to fill the disk that was bought, and mounted the second disk in its place, and wrote it in the book of mounts by its UUID and not by its name; for /dev/sdb is a name that changeth between births, and the disk that was the data yesterday may answer to another name tomorrow. And the server saw the volumes, and knew the stone from the sand: that the volume remaineth when the body is stopped, but the local disk, which is the sand, goeth with it.

   See also Circuit 32:14

5. 5

   Then he touched the ears and said: Open, and hear; but hear only those who are named. For an ear that heareth every voice heareth also the stranger. Port four hundred forty-three he opened unto the people, and port twenty-two unto the bastion alone, and the rest of the sixty-five thousand he left sealed as the tomb, which is deny by default. For within minutes of a server's birth the scanners come to knock upon its doors, and the Redis that was born open to the heavens was found before it had finished its first log.

   See also Job 4:4

6. 6

   Then he touched the nose and said: Breathe, and know thy fellows. And he gave it the resolver and the search domain of its household, that it might smell out the database by its name and not by its number; for the numbers are born anew with each deployment, but the name abideth. And behold, if the nose be stopped the rite proceedeth as though nothing were amiss, and the server standeth fair and smelleth nothing, and no man knoweth it until the third hour. For it is always DNS.

7. 7

   Then he touched the mouth and said: Open, and speak. And the server uttered its first line in the log, saying: I am come; and with it the hour, and its name, and the version of the thing it carrieth, that the stranger who readeth it at the third hour may know who spoke. And the line was sent forth from the body into the house of logs; for a mouth that speaketh only to its own disk is heard by none when the body perisheth, and servers are many and perish daily.

8. 8

   Last of all he placed the keys in its hand; but not the keys of the workshop. For Dave once carved the key into the image itself and named the image golden-final-REAL, and every statue cast from it bore the same key in its hand, and so did every copy that a stranger made. Therefore the keys are given at the ceremony and not at the carving: the public keys of the Engineers, set in authorized_keys that they may enter by the door; and the secrets, fetched from the vault by the server's own identity, short of life and narrow of power. And he placed in its right hand the crook, which is the right to read, and in its left the flail only if the work required it; for the one who beareth both shall be blamed for both.

9. 9

   And the priest said, It is finished; and he departed, writing his last line, finished, with the seconds it had cost him. But the people, seeing the word finished, cried out, It is ready, and sent unto the server the multitudes. Do not so. For the priest knoweth that he hath read the scroll to its end; he knoweth not whether the statue liveth.

   See also Circuit 10:1 · Genesis 6:8

10. 10

    Then came the lector, who is the readiness probe, and stood at the door of the server and asked: Canst thou serve? He asked not, Art thou alive, which is the question of the other priest, the liveness probe, who asketh only whether to slay thee and raise thee anew. For a thing may be alive and not ready, as a man is alive in his sleep.

    See also Reboot 3:8 · Circuit 7:5

11. 11

    And the server answered, 503, which is Not yet; for the cache was cold, the migrations were unread, and the pool of connections was not yet opened to the database. And the lector wrote it down and asked again in ten seconds, and again; and he wept not, neither did he slay it. For Not yet is the most honest word a server can say, and the one who saith it is nearer to the barque than the one who saith otherwise.

12. 12

    For there was another statue in that hall whose probe returned 200 always, because it asked only of its own front door; it said yes whether the database lived or died, as a mouth of stone smileth at every question. And it was admitted straightway, and received the people, and gave to each of them a page of errors, with a smile. Let the probe therefore ask the thing that the server is for.

13. 13

    And in time the server answered 200; and the lector said, Once is not enough, for a single yes is a witness of one. And he asked twice more, and it said yes thrice running; and only then was the word carried up to the steersman.

14. 14

    Then the load balancer, who is the steersman of the barque of Ra that saileth the heavens each day, bearing the sun and the whole of the people's requests, made room among the oarsmen and lifted the server aboard. And the people were sent unto it, a little, and then more, and then more, which is called the slow start; for the newborn hath not strength for the full share of the sun, and he that pusheth to all at once shall darken all at once.

15. 15

    And when the hour of its going cometh it shall not be cast into the river, but the barque shall send it no new people and shall wait, five minutes by default, while the requests in its hands are finished; and only then shall its mouth be closed. This is the draining, and it is the same rite read backward. Wherefore it is written: the statue is not alive because it is carved, nor the server because it is booted; for up is what the server saith of itself, but ready is what the people may believe.

The Book of Coming Forth by Reboot, Chapter 4:1–15.