Today I had an interesting problem. You know when there are DNS issues, usually it is quite obvious – but sometimes it really isn’t – everything seems to be working – ish – but just not as fast as you’d hope.
As you know – DNS was always THE mandatory requirement for any VMware solution – but not just forward DNS, but reverse DNS as well.
Take NSX – I have implemented an NSX solution for a customer which was great and working as expected but now coming back to said customer we noticed that the web client plugin is pretty much useless.
It works – but it takes a LOONG time to load anything really. So for instance, fire up the web client, go to Network & Security and try to go to the NSX Managers view in order to configure some IP Sets.
In this environment – clicking said option took about 5 minutes to load. 5 minutes to load the NSX Manager view, 5 minutes to load the tabs and then another 5 minutes to load the select option.
Needless to say it wasn’t workable – I have no idea how the customer managed to configure endless Logical Switches without losing ‘it’ – I certainly would have.
A bit of drilling down revealed that the primary NSX Manager was configured with a different set of DNS servers than the Secondary NSX Manager. Not just different as in, site specific, but different from their internal setup point of view.
The primary manager was configured with a DNS server that does not hold any reverse DNS zones or at least they weren’t configured / removed.
That fixed (followed by a sub-sequent reboot of the NSX Manager to clear the cache) fixed the speed issue.
So the bottom line – even if things appear to be working – but the speed isn’t what you’d expect – check DNS !!