curl'ing service fails (times out) unless made from node not hosting the pod
On both labs 2 (curl a service (pod is on the worker) from master), and lab 3 (curl registry on port 5000 running on worker from master), my network calls time out. If i issue the same curl statement from the worker it works. this indicates that inter-node http traffic is blocked or failing. My two VMs are deployed on GCP on the default VPC. I have verified that I have a firewall rule enabling all traffic on all ports internally between machines. i read on a forum thread that apparmor could also possibly get in the way so i terminated that service on both nodes. i'm at my wit's end as to why i can't make an http call from master to worker. the hint on page 21 of the lab instructions (chapter 3) is not specific enough to allow me to figure out the proper way to configure GCP: "if the connection hangs it may be due to a firewall issue; ..ensure your instances are running using VPC setup and all ports are allowed.." -- please provide explicit steps. thanks.
Comments
-
thinking about this further.. since my cluster is up and my worker joined it, and commands from master such as
kubectl get nodes
indicate that the two nodes are communicating just fine, i must conclude this issue has nothing to do with the vpc setup in gcp. i suspect it has to do with how kube-proxy and iptables are configured perhaps..0 -
i'm looking at the k8smaster.sh script, it issues kubeadm init with --pod-network-cidr of 192.16.8.0.0/16, but my clusterip is in the 10.99 range. i wonder if perhaps the --service-cidr flag should accompany that command?
0 -
Hi @EitanSuez,
The cluster IP is expected to be in a different IP range because it is not a pod, thus will not receive an IP from the range specified for pods.
The default VPC on GCP may be blocking some ports - it is a strange behavior even when you create a firewall rule to open all ports, and you expect all traffic to go thru. The suggestion from prior posts is that you create a new VPC with a new firewall rule open to all traffic, and add your VM instances in this custom VPC.
Ubuntu on GCP typically has ufw (Ubuntu firewall) inactive, but it can't hurt to verify that too, to make sure it is not active and blocking some of the ports.
Regards,
-Chris0 -
Thanks Chris, I'll give that a go today and report back..
0 -
yep, worked like a charm! i can confirm that when i create my own vpc and add in my own allow-internal firewall rule to that vpc, then the problem i describe above does not manifest itself.
0
Categories
- All Categories
- 60 LFX Mentorship
- 113 LFX Mentorship: Linux Kernel
- 618 Linux Foundation IT Professional Programs
- 321 Cloud Engineer IT Professional Program
- 142 Advanced Cloud Engineer IT Professional Program
- 55 DevOps Engineer IT Professional Program
- 68 Cloud Native Developer IT Professional Program
- 6 Express Training Courses
- 6 Express Courses - Discussion Forum
- 2.3K Training Courses
- 19 LFC110 Class Forum - Discontinued
- 9 LFC131 Class Forum
- 31 LFD102 Class Forum
- 175 LFD103 Class Forum
- 22 LFD121 Class Forum
- 2 LFD137 Class Forum
- 61 LFD201 Class Forum
- 2 LFD210 Class Forum
- 1 LFD210-CN Class Forum
- 1 LFD213 Class Forum - Discontinued
- 128 LFD232 Class Forum - Discontinued
- LFD237 Class Forum
- 23 LFD254 Class Forum
- 653 LFD259 Class Forum
- 108 LFD272 Class Forum
- 1 LFD272-JP クラス フォーラム
- 4 LFD273 Class Forum
- 2 LFS145 Class Forum
- 28 LFS200 Class Forum
- 740 LFS201 Class Forum - Discontinued
- 1 LFS201-JP クラス フォーラム
- 12 LFS203 Class Forum
- 92 LFS207 Class Forum
- 301 LFS211 Class Forum
- 54 LFS216 Class Forum
- 47 LFS241 Class Forum
- 41 LFS242 Class Forum
- 37 LFS243 Class Forum
- 12 LFS244 Class Forum
- 41 LFS250 Class Forum
- 1 LFS250-JP クラス フォーラム
- LFS251 Class Forum
- 142 LFS253 Class Forum
- LFS254 Class Forum
- LFS255 Class Forum
- LFS256 Class Forum
- LFS257 Class Forum
- 1.2K LFS258 Class Forum
- 10 LFS258-JP クラス フォーラム
- 106 LFS260 Class Forum
- 145 LFS261 Class Forum
- 39 LFS262 Class Forum
- 83 LFS263 Class Forum - Discontinued
- 15 LFS264 Class Forum - Discontinued
- 11 LFS266 Class Forum - Discontinued
- 20 LFS267 Class Forum
- 18 LFS268 Class Forum
- 26 LFS269 Class Forum
- 204 LFS272 Class Forum
- 1 LFS272-JP クラス フォーラム
- LFS274 Class Forum
- 3 LFS281 Class Forum
- 249 LFW211 Class Forum
- 177 LFW212 Class Forum
- 9 SKF100 Class Forum
- SKF200 Class Forum
- 907 Hardware
- 220 Drivers
- 74 I/O Devices
- 44 Monitors
- 116 Multimedia
- 210 Networking
- 102 Printers & Scanners
- 86 Storage
- 764 Linux Distributions
- 88 Debian
- 66 Fedora
- 15 Linux Mint
- 13 Mageia
- 24 openSUSE
- 143 Red Hat Enterprise
- 33 Slackware
- 13 SUSE Enterprise
- 357 Ubuntu
- 482 Linux System Administration
- 40 Cloud Computing
- 70 Command Line/Scripting
- Github systems admin projects
- 95 Linux Security
- 80 Network Management
- 108 System Management
- 51 Web Management
- 72 Mobile Computing
- 25 Android
- 32 Development
- 1.2K New to Linux
- 1.1K Getting Started with Linux
- 545 Off Topic
- 132 Introductions
- 223 Small Talk
- 22 Study Material
- 831 Programming and Development
- 282 Kernel Development
- 515 Software Development
- 974 Software
- 260 Applications
- 185 Command Line
- 3 Compiling/Installing
- 119 Games
- 318 Installation
- 65 All In Program
- 65 All In Forum
Upcoming Training
-
August 20, 2018
Kubernetes Administration (LFS458)
-
August 20, 2018
Linux System Administration (LFS301)
-
August 27, 2018
Open Source Virtualization (LFS462)
-
August 27, 2018
Linux Kernel Debugging and Security (LFD440)