Wired Intelligent Edge

 View Only
last person joined: 17 hours ago 

Bring performance and reliability to your network with the HPE Aruba Networking Core, Aggregation, and Access layer switches. Discuss the latest features and functionality of your switching devices, and find ways to improve security across your network to bring together a mobile-first solution
Expand all | Collapse all

Strange DNS resolver issue on VSX switches

This thread has been viewed 17 times
  • 1.  Strange DNS resolver issue on VSX switches

    Posted 28 days ago

    Hi 

    We have some redundant VSX stacks of CX8360 running 10.10.1090 and we have issues with connectivity to central from the MGMT interface.
    My working theory is that the problem is caused by failed DNS lookups (see below)

    The interface is configured with a static IP and a static gateway:

    interface mgmt
        no shutdown
        ip static 172.26.0.5/16
        default-gateway 172.26.0.1

    The config also contains these DNS entries:

    ip dns server-address 172.16.10.7 vrf mgmt
    ip dns server-address 172.24.10.5 vrf mgmt
    ip dns server-address 172.16.10.5 vrf mgmt

    But when I login to the switch any attempt at name resolution fails with "temporary name resolution failure" when trying to ping names from MGMT. 

    The MGMT vrf and interface has internet connectivity as I can ping 8.8.8.8 with the command "ping 8.8.8.8 vrf MGMT"
    The same command can also ping all of the DNS servers.

    I tried using start-shell and have a look at /etc/resolv.conf, but that contains no DNS servers - regardless if I enter some into the config without the appended "vrf mgmt".
    On my other CX switches all entered DNS servers in the config ends up in /etc/resolv.conf

    Any idea what causing the DNS resolver issue (and likely the central connectivity issue)?

    Cheers.



  • 2.  RE: Strange DNS resolver issue on VSX switches

    Posted 28 days ago
    You could try :
    interface mgmt
        no shutdown
        ip static 172.26.0.5/16
        default-gateway 172.26.0.1
        nameserver 172.16.10.7 172.24.10.5
    (only two is allowed)



    ------------------------------
    Arne Opdal
    ------------------------------



  • 3.  RE: Strange DNS resolver issue on VSX switches

    Posted 27 days ago

    -




  • 4.  RE: Strange DNS resolver issue on VSX switches

    Posted 27 days ago

    Excellent - That did the trick :-)

    Thank you very much.