Errata for The Practice of Cloud System Administration

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Fixed in the 2nd Printing

Section 1.5.1 - page 21

consistant -> consistent

Section 1.5.3 - page 24

"Finally, systems such as Cassandra, Risk, and Dynamo [...]" (Risk -> Riak). The accompanying graphic has correct spelling.

Section 2.1.6 - page 37

Typo: Change "though" to "through" in the sentence /may work though "luck"/.

(Fixed in the third printing)

Section 3.5 - page 67

Typo: In the second to last sentence of the "Implement Ephemeral Computing" bullet, "short span time" should be "short time span".

Section Section 3.1.2 - page 55

"Some offer more more esoteric services" (Remove the extraneous "more".)

(Fixed in the third printing)

Section 4.2.1 - page 74

"The header is called X-Forwarded-For:. The first proxy or load balancer adds the header, the original client IP address, and its own IP address. Additional proxies and load balancers append their own IP addresses. Although web servers generally log the client IP address, all the intervening IP addresses can also be accessed by the application."

This spirit of that is correct but it isn't technically accurate. New printings will say:

"This header is called X-Forwarded-For:. It contains a list of IP addresses starting with the client's and includes all the previous proxies or load balancers that the request has passed through. Note that the client and intermediate devices can add invalid or forged addresses to the list. Therefore you can only trust the address added by your own load balancer. Using the rest is insecure and risky."

Section 4.6.1 - page 86

"The message bus master learns the underlying physical network topology[...]" Remove the word "physical".

Section 6.6.1 - page 132

"File systems such as ZFS, BTFS, and Hadoop HDFS" (BTFS -> Btrfs)

Section 10.4.3 - page 219

"When tuning up hundreds of machines" (tuning -> turning)

Section 13.6 - page 282

Delete the extraneous word "it" from:

"Save the suggestions on how to use it the template more properly for one-on-one feedback."

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Fixed in the 3rd Printing

Section 13.1.1 - page 276

Delete extraneous "new" from "new new router configuration".

Section 15.1.2

The case study that begins on page 310 is titled "Repeating Risky Behavior to Reduce Risk". It change "Behavior" to "Procedures" to match the text.

Section 15.4.3 - page 318

Under the "Planning" heading, the last sentence of the first sentence should read, "During the actual test, the proctor is responsible for the test's execution."

Section 16.3 - page 336

"The median number of items in a shopping card" ("card"-> "cart")

Section D.1 - page 481

Remove extraneous "s" from "Reviewers(s)" and "Approvers(s)"

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Fixed in the next Printing

Section 5.4.5 - page 108

"entries will be eventually be" (remove the first "be")

Section 6.3.1 - page 125

The statement 168/1,000,000 × 100 = 1.7 percent, or 1 in 60 should be 168/100,000 * 100 = 0.17% or 1 in 600

Section 6.6.3 - page 135

"If a loss of heartbeat is detected, the secondary takes over and becomes the active load balancer. Any TCP connections that were "in flight" are disconnected since the primary is unaware of them."

To be clear "the primary" should be "the new primary".

Chapter 17 - page 350

On page 350, Java Counters sidebar: 2nd last word should be unsigned not signed.