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# citrix-netscalers
Slackbot
12/12/2019, 4:32 PMThis message was deleted.
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CTXMike
12/12/2019, 4:45 PMIf you’re getting multiple addresses back then you probably have the MIR option enabled. https://docs.citrix.com/en-us/citrix-adc/13/global-server-load-balancing/how-to/protect-setup-against-failure.html
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Kevin Schwartzmiller
12/12/2019, 6:09 PMWell that looked hopeful... but MIR is disabled.
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CTXMike
12/12/2019, 6:10 PMonly other time i can think of when you get multiple IPs in response is if the service is down
CTXMike
12/12/2019, 6:10 PM“When a GSLB virtual server is disabled or in a DOWN state, the response to a DNS query for the GSLB domain bound to that virtual server contains the IP addresses of all the services bound to the virtual server.”
CTXMike
12/12/2019, 6:11 PMYou can enable Empty Down Response (EDR) to make it respond with an empty A record if you want. if neither of those things are in place then you might need to ring up support and have them take a look.
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Kevin Schwartzmiller
12/12/2019, 6:14 PMThanks @CTXMike... looks like I may have to go down that route (support case).
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CTXMike
12/12/2019, 6:15 PMone quick thing you can do to rule out an intermediate DNS server caching weird responses is to do an nslookup directly against the ADNS service IP, that’s helped me in troubleshooting before
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Kevin Schwartzmiller
12/12/2019, 6:19 PMDirectly against the ADNS service I get two responses from one of them... and again, one server response from the other.
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CTXMike
12/12/2019, 6:20 PMinteresting. GSLB config doesn’t sync automatically, perhaps check the one that’s reporting multiple IPs and make sure it doesn’t have MIR set/think the vserver is down somehow?
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Kevin Schwartzmiller
12/12/2019, 6:21 PMOpps, that was my bad.. I had disable the GSLB vserver when I was doing a test.. after enabling it and going against the ADNS server IP I am getting 1 server response from both..
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CTXMike
12/12/2019, 6:21 PMcool!
CTXMike
12/12/2019, 6:22 PMknew it had to be something simple, GSLB is pretty straightforward in most cases.
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Kevin Schwartzmiller
12/12/2019, 6:25 PMSo when taking out one side of a particular GSLB domain... is the proper way to disable that particular side's GSLB vserver?
Kevin Schwartzmiller
12/12/2019, 6:26 PMOr is it to disable the bound GSLB service?
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CTXMike
12/12/2019, 6:26 PMNope, what you want to do is disable that side’s GSLB service. that way no matter which NS gets the DNS request it responds appropriately. You should be able to do that from one NS and perform a GSLB sync to propagate that change to all NSes currently participating in GSLB.
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Kevin Schwartzmiller
12/12/2019, 6:27 PMyeah, that makes sense.
Kevin Schwartzmiller
12/12/2019, 6:27 PMThanks for the GSLB 101 😉
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CTXMike
12/12/2019, 6:27 PMglad to help!
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Kevin Schwartzmiller
12/12/2019, 6:29 PMDo you see a lot of people using the EDNS Client Subnet setting?
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CTXMike
12/12/2019, 6:33 PMIf you’re doing anything like proximity based GSLB then definitely, otherwise it doesn’t necessarily make a functional difference.
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Kevin Schwartzmiller
12/12/2019, 6:37 PMOk, thank you again