# Cross-Host communication
**URL:** https://forums.suse.com/t/cross-host-communication/5005
**Category:** Rancher 1.x
**Created:** [December 23, 2016, 2:01pm UTC](https://forums.suse.com/t/cross-host-communication/5005 "2016-12-23T14:01:38Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@salvax86](https://forums.suse.com/u/salvax86)
#### Post date: [December 23, 2016, 2:01pm UTC](https://forums.suse.com/t/cross-host-communication/5005/1 "2016-12-23T14:01:39Z")
Hello together,
I have kind a question about cross-host communication between containers.
Scenario:
- I have 10 AWS-EC2 Instances with Ubuntu15.10, Docker 1.12.5 and Rancher 1.2.1
- By set up all clusters (kafka, zookeeper and applications using kafka), everything is working fine
- After three days I can observe following behaviour:
\*\* I name the ec2 instances, where kafka-containers are run, kafka-1…kafka-x
\*\* Communication from kafka-1…kafka-x containers to other EC2 instances’ containers is working
\*\* Communication from kafka-1 containers to kafka-2,…,kafka-x is not working
\*\* ping command confirms the issue: I can ping from kafka containers to other instances’ containers. If i want to ping from kafka-1 containers to other kafka-instances containers, it is not working
\*\* I use managed network for kafka containers. Default Network for every stack/service
Solution:
- A restart of ipsec (rancher/net:v0.7.5) will restart the healthcheck and kafka-container too and the problem is gone. After 3 days it’s happening again.
- I went through [http://docs.rancher.com/rancher/v1.2/en/faqs/troubleshooting/](http://docs.rancher.com/rancher/v1.2/en/faqs/troubleshooting/) and everything seems ok
- No limitation about security groups and vpn rules on AWS Instances
How can I avoid this behaviour?
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### Author:  [@salvax86](https://forums.suse.com/u/salvax86)
#### Post date: [March 9, 2017, 6:22pm UTC](https://forums.suse.com/t/cross-host-communication/5005/2 "2017-03-09T18:22:06Z")
The problem seems to be like in this topic: [IPSec network fails silently on a host](http://forums.suse.com/t/ipsec-network-fails-silently-on-a-host/5471/9)