weizhouapache commented on issue #7364: URL: https://github.com/apache/cloudstack/issues/7364#issuecomment-1486292044
@Atiqul-Islam thanks for the update. see my replies inline. > @weizhouapache > > Appreciate the help. Listed below are answers to your questions. > > * I am able to ping google from the CloudStack Virtual Router. > * I am able to ping google from the VM I quickly spun up using the centos template that comes with cloudstack. from what I understand, the centos template runs on the different host as the CloudStack Virtual Router, right ? > * One of the KVM host and the Management Server is running on 1 bare metal physical ubuntu system, the second host is running on another baremetal physical ubuntu system. > > **_Additional Tests I performed_** > > Based on what I came across so far, my mtu size for ` interface B` (the interface associated to the VXLAN isolation) is 1500 same as the other interface which is associated to the VLAN. Do you think the mtu size of 1500 is causing the problem. > Yes, it is my suspicion. nested environments might have some issues cased by mtu size. From what you said below, it seems mtu size caused the ubuntu installation to be stuck. > Also what is the recommended mtu size for VXLAN isolation in Cloud Stack > > I tried configuring the mtu size of cloudbr1 to 1550, that seemed to have resolved the issue on the VM running on the same host as the virtual router, I was able to install Ubuntu there without any issues. However now I am having issues with VM on the second host. > > Issues I am having right now: The ubuntu installation process on the VM running on the host (without the virtual router) is unable to connect to the internet and as a result is stuck at the curlin command. I find the behavior really weird and unexplainable as I am able to ping google.com and curl google.com from another VM with centos template running on the same host. can you check the virtual router during the ubuntu installation ? - check /var/log/dnsmasq.log to ensure the ubuntu vm gets the correct IP - check if the IP is reachable (by ping) - use tcpdump to see if there are some packets during the process since the kvm hosts are running on top of ubuntu physical server, have you configured the mtu size of the virtual nics of the kvm hosts on the physical servers ? > > **_Note:_** **I am using the same ISO to install Ubuntu on both the VMs. On the VM instance (associated to the host connected to the virtual router) the installation process runs fine and updates from the internet as required. In the second VM (on the host without the virtual router) the installation process is unable to connect to the internet and gets stuck. Both the VMs are on the same network.** > > _Something I noticed that even though I didn't explicitly mention storage network, the storage network was added to `cloudbr0` along with the management network. This makes me wondering if that is causing any issue as the `cloudbr0` is connected to an access or untagged port on the switch. But it seems like cloudbr0 is being used for both the management and the storage network._ > that's expected. If storage network is not specified, the management network will be used as storage network. > Let me know if you have any more questions, or would like to look at any network details. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
