mtu 1500 qdisc pfifo\_fast state UP qlen 1000
link/ether 00:50:56:ab:6b:7e brd ff:ff:ff:ff:ff:ff
inet 192.168.1.27/24 brd 192.168.1.255 scope global ens32
( h3c fw dnat : 112.112.112.1:8080—\>192.168.1.26:8080)
On Host A:
docker run -d --restart=always -p 8080:8080 rancher/server
open the url: 112.112.112.1:8080
then add host A:
sudo docker run -e CATTLE\_AGENT\_IP= **192.168.1.26**
-d --privileged -v /var/run/docker.sock:/var/run/docker.sock -v /var/lib/rancher:/var/lib/rancher rancher/agent:v0.9.2 [http://112.112.112.1:8080/v1/scripts/1889F6AEE8DAE97968BC:1457794800000:A4rZOfxsh2yVvTzUtRpXLXnNms](http://112.112.112.1:8080/v1/scripts/1889F6AEE8DAE97968BC:1457794800000:A4rZOfxsh2yVvTzUtRpXLXnNms)
then add host B:
sudo docker run -d --privileged -v /var/run/docker.sock:/var/run/docker.sock -v /var/lib/rancher:/var/lib/rancher rancher/agent:v0.9.2 [http://112.112.112.1:8080/v1/scripts/52A2A908C43C77A0B7E4:1457791200000:oJ9DZ0VHpVnwDg0lpXxg1o7mu9M](http://112.112.112.1:8080/v1/scripts/52A2A908C43C77A0B7E4:1457791200000:oJ9DZ0VHpVnwDg0lpXxg1o7mu9M)
my problem is:
Containers started on the same host can ping each other, but containers on different hosts do not see each other.
I can’t confirm whether I started rancher-agent ：-e CATTLE\_AGENT\_IP= **192.168.1.26**
please help me?thanks.
---
### Author:  [@denise](https://forums.suse.com/u/denise)
#### Post date: [March 13, 2016, 6:31am UTC](https://forums.suse.com/t/again-cross-host-intercontainer-communication-trouble/2014/2 "2016-03-13T06:31:45Z")
Do you have UDP ports 500 and 4500 open on both hosts? These are required for the IPSec networking to work.
---
### Author:  [@hosthouse](https://forums.suse.com/u/hosthouse)
#### Post date: [March 13, 2016, 6:48am UTC](https://forums.suse.com/t/again-cross-host-intercontainer-communication-trouble/2014/3 "2016-03-13T06:48:05Z")
yes, docker ps -a, i can see .
but:
on 192.168.1.26.
nc -u 192.168.1.27 4500
on 192.168.1.27.
nc -u 192.168.1.26 4500
not success.
---
### Author:  [@denise](https://forums.suse.com/u/denise)
#### Post date: [March 22, 2016, 9:53pm UTC](https://forums.suse.com/t/again-cross-host-intercontainer-communication-trouble/2014/4 "2016-03-22T21:53:33Z")
Do the hosts have the correct IP on the UI?
---
### Author:  [@wolli-lenzen](https://forums.suse.com/u/wolli-lenzen)
#### Post date: [April 26, 2016, 10:27am UTC](https://forums.suse.com/t/again-cross-host-intercontainer-communication-trouble/2014/5 "2016-04-26T10:27:56Z")
same issue here
I have 2 hosts (boot2docker 1.11.0) running on vSphere VMs.
- 172.16.99.105
- 172.16.99.106
VMs can ping each other.
All containers on one host can ping each other on the managed network, but communication to containers on the other host isn´t possible over the managed network.
It looks like 500/UDP and 4500/UDP aren´t mapped correctly into the rancher/agent-instance:v0.8.1
nc -u 172.16.99.105 4500 doesn´t get a connection on 172.16.9.106 and vice versa
docker ps shows
897ebd05a0ca rancher/agent-instance:v0.8.1 “/etc/init.d/agent-in” 8 minutes ago Up 8 minutes 0.0.0.0:500-\>500/udp, 0.0.0.0:4500-\>4500/udp 07e33149-ac58-4400-885e-9c3fef432f34
0.0.0.0:500-\>500/udp, 0.0.0.0:4500-\>4500/udp -\> is this correct??
shouldn´t it be simply 500-\>500/udp on a host with one interface, or bound to the interface IP like 172.16.99.105:500-\>500/udp
---
### Author:  [@wolli-lenzen](https://forums.suse.com/u/wolli-lenzen)
#### Post date: [April 26, 2016, 10:39am UTC](https://forums.suse.com/t/again-cross-host-intercontainer-communication-trouble/2014/6 "2016-04-26T10:39:16Z")
one more note
if I go to edit the network agent in UI, there is a posibility to set [IP:]Port for ipSec Communication between hosts. it is by default mapped 4500-\>4500/udp and 500-\>500/udp
If I put the correct pubic hostIP in front like 172.16.99.105:4500 , save and than go back again, only 172 is saved in the field, so it looks like it´s not allowed to enter IP address in the field, even if the helptext says so