Kubectl exec .. -- /bin/bash doesn't connect

Question

recently I've been unable to connect to the bash on my kubernetes cluster. And I'm at a loss as to why. Have anyone else experienced this?

What happened: I can no longer connect to /bin/bash in my running pods. It simply hangs when trying to exec the command. I've verified that bash is installed (/bin/bash --version). I've tried both locally and from the google cloud console

What you expected to happen: That my local terminal successfully connects to the pods bash terminal

How to reproduce it (as minimally and precisely as possible): I've only tested it on my cluster, but the command I'm running is:

kubectl exec -i POD_ID --namespace=NAMESPACE -c CONTAINER -- /bin/bash

I've also run it with DEBUG=1 which results in the following:

DEBUG=1 kubectl exec -i POD_ID --namespace=NAMESPACE -c CONTAINER -- 
/bin/bash
I0412 10:52:14.560443    2675 logs.go:41] (0xc4200aed10) 
(0xc420242140) Create stream
I0412 10:52:14.560486    2675 logs.go:41] (0xc4200aed10) 
(0xc420242140) Stream added, broadcasting: 1
I0412 10:52:14.611561    2675 logs.go:41] (0xc4200aed10) Reply frame 
received for 1
I0412 10:52:14.611658    2675 logs.go:41] (0xc4200aed10) 
(0xc4203e26e0) Create stream
I0412 10:52:14.611692    2675 logs.go:41] (0xc4200aed10) 
(0xc4203e26e0) Stream added, broadcasting: 3
I0412 10:52:14.656684    2675 logs.go:41] (0xc4200aed10) Reply frame 
received for 3
I0412 10:52:14.656725    2675 logs.go:41] (0xc4200aed10) 
(0xc4202425a0) Create stream
I0412 10:52:14.656737    2675 logs.go:41] (0xc4200aed10) 
(0xc4202425a0) Stream added, broadcasting: 5
I0412 10:52:14.702100    2675 logs.go:41] (0xc4200aed10) Reply frame 
received for 5
I0412 10:52:14.702140    2675 logs.go:41] (0xc4200aed10) 
(0xc420659680) Create stream
I0412 10:52:14.702151    2675 logs.go:41] (0xc4200aed10) 
(0xc420659680) Stream added, broadcasting: 7
I0412 10:52:14.746707    2675 logs.go:41] (0xc4200aed10) Reply frame 
received for 7

Anything else we need to know?:

Environment: - Kubernetes version

Client Version: version.Info{Major:"1", Minor:"8", 
GitVersion:"v1.8.6", 
GitCommit:"6260bb08c46c31eea6cb538b34a9ceb3e406689c", 
GitTreeState:"clean", BuildDate:"2017-12-21T06:34:11Z", 
GoVersion:"go1.8.3", Compiler:"gc", Platform:"darwin/amd64"}
Server Version: version.Info{Major:"1", Minor:"9+", 
GitVersion:"v1.9.6-gke.0", 
GitCommit:"cb151369f60073317da686a6ce7de36abe2bda8d", 
GitTreeState:"clean", BuildDate:"2018-03-21T19:01:20Z", 
GoVersion:"go1.9.3b4", Compiler:"gc", Platform:"linux/amd64"}

• Cloud provider or hardware configuration: Google Cloud

• OS (e.g. from /etc/os-release):

  PRETTY_NAME="Debian GNU/Linux 9 (stretch)" NAME="Debian GNU/Linux" VERSION_ID="9" VERSION="9 (stretch)" ID=debian HOME_URL="https://www.debian.org/" SUPPORT_URL="https://www.debian.org/support" BUG_REPORT_URL="https://bugs.debian.org/"

• Kernel (e.g. uname -a): Linux bounce-deployment-f95687cbc-mfgtg 4.4.111+ #1 SMP Thu Feb 1 22:06:37 PST 2018 x86_64 GNU/Linux

• Install tools:
• Others:

Answer 1

You have to pass -t to kubectl exec command, just like docker exec -i -t <container_name> bash.

From the help command:

-t, --tty=false: Stdin is a TTY