julien-duponchelle
commented
7 years ago How do you connect the GUI to remote server? You use a VPN?
Open cvazquez-edge opened 7 years ago
julien-duponchelle
commented
7 years ago How do you connect the GUI to remote server? You use a VPN?
cvazquez-edge
commented
7 years ago I've used a couple methods. I can replicate the issue on the CLI using dynagen, and also running gns3server and remotely tunneling in with SSH in a VPN.
GNS3 GUI seems to have no trouble connecting and issuing commands to gns3server and dynamips.
Thanks!
julien-duponchelle
commented
7 years ago A SSH tunnel will bug because on the remote the other side of the tunnel will be see as 127.0.0.1.
Both dynamips need to have different IP and be able to communicate with each other via all the port.
In this script you have a sample for setting up an OpenVPN: https://github.com/GNS3/gns3-server/blob/master/scripts/remote-install.sh
cvazquez-edge
commented
7 years ago I don't think the SSH or VPN are an issue here.
I'm having this problem running all the simulations on the same AWS instance. This bad behavior occurs with a single dynamips instance running in hypervisor mode and controlled locally by dynagen, with two routers simulated. It also occurs with a local instance of gns3server starting two separate instances of dynamips locally (one for each router), and controlled remotely by the GNS3 GUI.
I haven't tried splitting the simulation load between my local machine and AWS. My goal here is to have a long term simulation running 100% on AWS, for testing some network management tools and producing realistic monitoring data. If they leak memory or fall over eventually, that's fine - I'll just have them restarted.
Other complications of this setup are docker and its bridges are running there too. Along with a TAP interface and a GRE and IPIP tunnel to another host. Connecting dynamips to tap0 works, and pinging that simulated router from the native host, or from across the GRE tunnel both work. Just inter-simulated router traffic fails.
julien-duponchelle
commented
7 years ago How do you start dynamips?
I think you need to tell to it that he need to bind on 127.0.0.1 otherwise he bind on his public ip and the AWS firewall block it.
cvazquez-edge
commented
7 years ago When running with dynagen, I start it like this: /usr/local/bin/dynamips -H 7200 -l /var/log/dynamips.log
When gns3server starts it, it's like this: Starting Dynamips: ['/usr/local/bin/dynamips', '-N1', '-l', 'dynamips_i3_log.txt', '-H', '55369']
Both bind to 0.0.0.0:7200, and when I start the sims, the 'nio create_udp' commands from dynagen or gns3 create those connections from 127.0.0.1:1000<->127.0.0.1:10001 etc.
Looks like the man page and CLI help have a discrepancy - I didn't realize I could give it an IP and port for '-H'.
Trying it like this: /usr/local/bin/dynamips -H 127.0.0.1:7200 -l /var/log/dynamips.log
I get the same behavior, except the hypervisor binds to 127.0.0.1 instead of 0.0.0.0. The UDP tunnel traffic still has the source address of eth0.
cvazquez-edge
commented
7 years ago I found a workaround. Instead of relying on dynagen (or GNS3 GUI) to infer and create the correct links, I specified the nio_udp parameters manually to use the eth0 address instead of localhost:
Broken dynagen .net snippet. Creates UDP connections to/from localhost:
[[ROUTER R1]]
model = 7200
idlepc = 0x6061aa54
f0/0 = R2 f0/0
s1/0 = R2 s1/0
[[router R2]]
model = 7200
idlepc = 0x6061aa54
# Implicit: f0/0 = R1 f0/0
# Implicit: s1/0 = R1 s1/0Working Dynagen.net snippet. Creates UDP connections to/from external IP, since that's where dynamips will source the traffic from anyway:
[[ROUTER R1]]
model = 7200
idlepc = 0x6061aa54
f0/0 = nio_udp:10000:<external IP>:10001
s1/0 = nio_udp:10002:<external IP>:10003
[[router R2]]
model = 7200
idlepc = 0x6061aa54
f0/0 = nio_udp:10001:<external IP>:10000
s1/0 = nio_udp:10003:<external IP>:10002Dynamips logs, much like before, but not using the loopback address for UDP tunnels:
Oct 05 20:54:56.707 HYPERVISOR: exec_cmd: nio create_udp nio_udp0 10000 <external IP> 10001
Oct 05 20:54:56.708 HYPERVISOR: exec_cmd: vm slot_add_nio_binding R1 0 0 nio_udp0
Oct 05 20:54:56.708 HYPERVISOR: exec_cmd: vm slot_add_binding R1 1 0 PA-8T
Oct 05 20:54:56.708 HYPERVISOR: exec_cmd: nio create_udp nio_udp1 10002 <external IP> 10003
Oct 05 20:54:56.709 HYPERVISOR: exec_cmd: vm slot_add_nio_binding R1 1 0 nio_udp1
Oct 05 20:54:56.709 HYPERVISOR: exec_cmd: vm slot_add_binding R2 0 0 C7200-IO-2FE
Oct 05 20:54:56.709 HYPERVISOR: exec_cmd: nio create_udp nio_udp2 10001 <external IP> 10000
Oct 05 20:54:56.709 HYPERVISOR: exec_cmd: vm slot_add_nio_binding R2 0 0 nio_udp2
Oct 05 20:54:56.710 HYPERVISOR: exec_cmd: vm slot_add_binding R2 1 0 PA-8T
Oct 05 20:54:56.710 HYPERVISOR: exec_cmd: nio create_udp nio_udp3 10003 <external IP> 10002
Oct 05 20:54:56.710 HYPERVISOR: exec_cmd: vm slot_add_nio_binding R2 1 0 nio_udp3 Netstat shows these connections:
udp 0 0 <external IP>:10000 <external IP>:10001 ESTABLISHED
udp 0 0 <external IP>:10001 <external IP>:10000 ESTABLISHED
udp 0 0 <external IP>:10002 <external IP>:10003 ESTABLISHED
udp 0 0 <external IP>:10003 <external IP>:10002 ESTABLISHEDI can now ping to/from R1 and R2 using ethernet and serial links. Traffic on the host still has the external IP as the source IP address, it just happens to be correct now.
It would be nice to figure out why dynamips is behaving badly in this environment, but not on others. Then I could go back to letting dynagen/GNS3 do more of the conveniences of counting ports and inferring the other sides of the links. That'll definitely get tedious with larger configs. But I'm not stuck anymore at least.
Thanks for looking into this! Still happy to provide logs or tcpdumps or whatever.
I've got an issue with dynamips 0.2.11 and 0.2.16 on an AWS instance of Ubuntu 14.04. All the links between simulated devices (ethernet and serial) are unable to pass any traffic. The key difference I see between this instance and a working instance on my Mac is that the UDP tunneled traffic on the loopback uses the wrong source IP.
Tcpdump on loopback for working instance on Mac OS X, pinging R2 FA0/0 from R1 FA0/0. All traffic is sourced from 127.0.0.1:
Broken instance on AWS Ubuntu 14.04, pinging R2 from R1. All pings and some other traffic are sourced from the external IP address of the AWS instance:
On the broken instance I see these logs:
And these Established UDP connections:
Appreciate any help, and I'm happy to produce more logs or test results, Chris Vazquez