csrfr

Distributed Services with Go: accessing the service outside the pods (Beta-4 pg.223)

Once deployed, I am not able to access the service outside the prolog pods. I can run the client successfully and access the service from a client running on one of the proglog pods.

However, I am not able to access the service from the following locations:

Laptop: The client connection hangs and then returns connection error while dialing dial tcp: lookup proglog-0.proglog.mysvcs.svc.cluster.local: no such host. I am dialing using the EXTERNAL-IP address of proglog-0 from k8s in the client (This address works when used from a proglog pod).
From a pod in the k8s cluster but not a proglog pod. It prints the following error repeatedly ERROR: 2020/10/31 18:59:29 [core] subconn returned from pick is not *acBalancerWrapper. Also, the acBalancerWrapper error appears when running the client from a proglog pod (where it usually works) from time to time.

Anyone faced this before, ideas?
At the moment I’m looking into GetServers returning the K8s DNS names (e.g. proglog-0.proglog.default.svc.cluster.local:8400 rather than the EXTERNAL-IP of the pods.

5 comments

#question /book-distributed-services-with-go

5 944 5

2021-03-04 05:18:40 UTC

Marked As Solved

travisjeffery

Author of Distributed Services with Go

Yeah we should return ErrNoSubConnAvailable like so:

func (p *Picker) Pick(info balancer.PickInfo) (
	balancer.PickResult, error) {
	p.mu.RLock()
	defer p.mu.RUnlock()
	var result balancer.PickResult
	if strings.Contains(info.FullMethodName, "Produce") ||
		len(p.followers) == 0 {
		result.SubConn = p.leader
	} else if strings.Contains(info.FullMethodName, "Consume") {
		result.SubConn = p.nextFollower()
	}
	if result.SubConn == nil {
		return result, balancer.ErrNoSubConnAvailable
	}
	return result, nil
}

so gRPC will block the RPC until a new picker is available with available sub connections.

Post #4

Also Liked

travisjeffery

Author of Distributed Services with Go

For 1. did you port-forward the pod/service to expose it outside k8s’ network? That’s what the $ kubectl port-forward pod/proglog-0 8400 8400 command in the book is for.

Could be because leader election is still underway so a nil subconn is returned for it.

Post #2

travisjeffery

Author of Distributed Services with Go

For 2. I think the error handling should be improved. I’m looking into it.

Post #3

Where Next?

View thread on forum

View Distributed Services With Go's book portal

Post errata for this book

Post a suggestion for this book

Post a question about this book

Post a review about this book

question

Home PragProg Customers

#question /book-distributed-services-with-go

5 944 5

Last post

Popular Pragmatic Bookshelf topics

PragProg Customers

Python Testing with pytest: pytest now requires markers to be declared (downloadable code)

Many tasks_proj/tests directories exist in chapters 2, 3, 5 that have tests that use the custom markers smoke and get, which are not decl...

#errata /book-python-testing-with-pytest

2 1383 2

2021-02-16 14:15:02 UTC

New

PragProg Customers

Apple Game Frameworks and Technologies: Screen image may be wrong (p 13)

Working through the steps (checking that the Info,plist matches exactly), run the demo game and what appears is grey but does not fill th...

#errata /book-apple-game-frameworks-and-technologies

11 1081 5

2021-05-15 17:31:07 UTC

New

PragProg Customers

Concurrent Data Processing in Elixir: various errata

Hi @Margaret , On page VII the book tells us the example and snippets will be all using Elixir version 1.11 But on page 3 almost the en...

#errata /book-concurrent-data-processing-in-elixir

15 1549 13

2021-04-11 17:34:47 UTC

New

PragProg Customers

Modern Front-End Development for Rails: Can't get TURBO_STREAM format in some cases

This isn’t directly about the book contents so maybe not the right forum…but in some of the code apps (e.g. turbo/06) it sends a TURBO_ST...

#question /book-modern-front-end-development-for-rails

1 1386 7

2021-04-04 21:22:11 UTC

New

PragProg Customers

Domain Modeling Made Functional: Missing diagram on page 18

The book has the same “Problem space/Solution space” diagram on page 18 as is on page 17. The correct Problem/Solution space diagrams ar...

#errata /book-domain-modeling-made-functional

1 1078 1

2021-09-11 17:34:22 UTC

New

PragProg Customers

The Ray Tracer Challenge: cannot pass scaling test (page 69-70)

The test is as follows: Scenario: Intersecting a scaled sphere with a ray Given r ← ray(point(0, 0, -5), vector(0, 0, 1)) And s ← sphere...

#question /book-the-ray-tracer-challenge

1 1093 4

2022-07-27 09:47:44 UTC

New

PragProg Customers

Programming Phoenix LiveView: Display Image Uploads (pdf p142)

The markup used to display the uploaded image results in a Phoenix.LiveView.HTMLTokenizer.ParseError error. lib/pento_web/live/product_l...

#errata /book-programming-phoenix-liveview

2 2102 9

2022-07-05 17:58:54 UTC

New

PragProg Customers

The Ray Tracer Challenge: Cannot get rid of acne When implement Shadows in Chapter 8.

Hi, I’m working on the Chapter 8 of the book. After I add add the point_offset, I’m still able to see acne: In the image above, I re...

#question /book-the-ray-tracer-challenge

1 1052 4

2024-07-09 23:10:34 UTC

New

PragProg Customers

Modern front-end development for Rails, second edition - Struggling to get the first chapter to work

After running /bin/setup, the first error was: The foreman' command exists in these Ruby versions: That was easy to fix: gem install fore...

#errata /book-modern-front-end-development-for-rails

1 1116 3

2023-06-22 14:09:32 UTC

New

PragProg Customers

Kotlin and Android Development featuring Jetpack: Transformations class doesn't seem to exist anymore (pp. 140-141

@mfazio23 Android Studio will not accept anything I do when trying to use the Transformations class, as described on pp. 140-141. Googl...

#errata /book-kotlin-and-android-development-featuring-jetpack

0 2155 5

2023-10-01 15:02:47 UTC

New

Other popular topics

General Dev>Dev Chat

HELLO WORLD (Introductions thread!)

Hello Devtalk World! Please let us know a little about who you are and where you’re from :nerd_face:

#community

481 6762 116

2025-11-06 03:57:03 UTC

New

General Dev>Learning Resources

A Common-Sense Guide to Data Structures and Algorithms, Second Edition

Algorithms and data structures are much more than abstract concepts. Mastering them enables you to write code that runs faster and more e...

pragprog.com

#pragprog /python /ruby #published-book /book-a-common-sense-guide-to-data-structures-and-algorithms-second-edition #math #algorithms /js

19 6022 5

2020-08-14 00:58:37 UTC

New

Linux>Questions

AMD or Intel for Programming with Linux as the OS?

I am thinking in building or buy a desktop computer for programing, both professionally and on my free time, and my choice of OS is Linux...

#mobile #android #web-development #linux #desktop-computer #mobile-development

36 6006 10

2020-07-12 20:50:05 UTC

New

General Dev>Dev Chat

Which language or framework do you want to learn next?

Curious to know which languages and frameworks you’re all thinking about learning next :upside_down_face: Perhaps if there’s enough peop...

#community #learning

243 6639 97

2025-12-01 07:17:12 UTC

New

General Dev>Code Editors

Onivim 2 Code Editor

Thanks to @foxtrottwist’s and @Tomas’s posts in this thread: Poll: Which code editor do you use? I bought Onivim! :nerd_face: https://on...

#code-editors /onivim /revery

88 6144 32

2023-05-15 07:32:26 UTC

New

General Dev>Hardware

BIIP MT3 Extended 2048 Custom Keycap Set (Drop)

This looks like a stunning keycap set :orange_heart: A LEGENDARY KEYBOARD LIVES ON When you bought an Apple Macintosh computer in the e...

/keyboards #apple #keycaps #mechanical-keyboards

14 6713 7

2020-12-12 19:58:26 UTC

New

General Dev>Dev Chat

The V Programming Language

The V Programming Language Simple language for building maintainable programs V is already mentioned couple of times in the forum, but I...

#programminguages /v

21 13874 7

2021-04-12 15:13:42 UTC

New

Backend>Learning Resources

Ash Framework

Explore the power of Ash Framework by modeling and building the domain for a real-world web application. Rebecca Le @sevenseacat and ...

pragprog.com

#pragprog /elixir #published-book /ash /book-ash-framework

15 7555 9

2025-02-06 12:19:21 UTC

New

Backend>Learning Resources

Simplicity

Fight complexity and reclaim the original spirit of agility by learning to simplify how you develop software. The result: a more humane a...

pragprog.com

#pragprog #published-book /book-simplicity

10 6553 8

2025-03-14 21:53:12 UTC

New

AI>Questions

What are the best text-to-speech ai generation tools that you can run locally?

Background Lately I am in a quest to find a good quality TTS ai generation tool to run locally in order to create audio for some videos I...

#ai #text-to-speech

6 7713 3

2025-03-24 16:48:39 UTC

New

Distributed Services with Go: accessing the service outside the pods (Beta-4 pg.223)

csrfr

Distributed Services with Go: accessing the service outside the pods (Beta-4 pg.223)

Marked As Solved

travisjeffery

Also Liked

travisjeffery

travisjeffery

Where Next?

Popular Pragmatic Bookshelf topics

Python Testing with pytest: pytest now requires markers to be declared (downloadable code)

Apple Game Frameworks and Technologies: Screen image may be wrong (p 13)

Concurrent Data Processing in Elixir: various errata

Modern Front-End Development for Rails: Can't get TURBO_STREAM format in some cases

Domain Modeling Made Functional: Missing diagram on page 18

The Ray Tracer Challenge: cannot pass scaling test (page 69-70)

Programming Phoenix LiveView: Display Image Uploads (pdf p142)

The Ray Tracer Challenge: Cannot get rid of acne When implement Shadows in Chapter 8.

Modern front-end development for Rails, second edition - Struggling to get the first chapter to work

Kotlin and Android Development featuring Jetpack: Transformations class doesn't seem to exist anymore (pp. 140-141

Other popular topics

HELLO WORLD (Introductions thread!)

A Common-Sense Guide to Data Structures and Algorithms, Second Edition

AMD or Intel for Programming with Linux as the OS?

Which language or framework do you want to learn next?

Onivim 2 Code Editor

BIIP MT3 Extended 2048 Custom Keycap Set (Drop)

The V Programming Language

Ash Framework

Simplicity

What are the best text-to-speech ai generation tools that you can run locally?

Latest in Distributed Services with Go

PragProg Customers

Latest on Devtalk

We ❤️ helpful members!

Categories:

Sub Categories:

Popular Portals

We're in Beta

Distributed Services with Go: accessing the service outside the pods (Beta-4 pg.223)

csrfr

Distributed Services with Go: accessing the service outside the pods (Beta-4 pg.223)

Marked As Solved

travisjeffery

Also Liked

travisjeffery

travisjeffery

Where Next?

Popular Pragmatic Bookshelf topics

Python Testing with pytest: pytest now requires markers to be declared (downloadable code)

Apple Game Frameworks and Technologies: Screen image may be wrong (p 13)

Concurrent Data Processing in Elixir: various errata

Modern Front-End Development for Rails: Can't get TURBO_STREAM format in some cases

Domain Modeling Made Functional: Missing diagram on page 18

The Ray Tracer Challenge: cannot pass scaling test (page 69-70)

Programming Phoenix LiveView: Display Image Uploads (pdf p142)

The Ray Tracer Challenge: Cannot get rid of acne When implement Shadows in Chapter 8.

Modern front-end development for Rails, second edition - Struggling to get the first chapter to work

Kotlin and Android Development featuring Jetpack: Transformations class doesn't seem to exist anymore (pp. 140-141

Other popular topics

HELLO WORLD (Introductions thread!)

A Common-Sense Guide to Data Structures and Algorithms, Second Edition

AMD or Intel for Programming with Linux as the OS?

Which language or framework do you want to learn next?

Onivim 2 Code Editor

BIIP MT3 Extended 2048 Custom Keycap Set (Drop)

The V Programming Language

Ash Framework

Simplicity

What are the best text-to-speech ai generation tools that you can run locally?

Latest in Distributed Services with Go

PragProg Customers

Latest on Devtalk

We ❤️ helpful members!

Devtalk Sponsors

Categories:

Sub Categories:

Popular Portals

Devtalk Sponsors

We're in Beta