DNS Troubleshooting using Nile Portal

dns troubleshooting using nile portal let's say if a customer reported saying that dns server is not reachable we need to first identify whether dns is not reachable for the end host device or its not reachable from the nsb elements to check if the dns is reachable or not from infrastructure (nile service blocks) 1 check the nile portal (np) dashboard → infrastructure → dns tile if green dns server(s) have passed nsb reachability → proceed further to check devices dns tile if red dns server(s) are failing nsb reachability → global dns issue 2\ click on the dns tile and check the availability status and experience nile portal dns availability info a)click on 8 8 8 8 / 192 168 1 9 (customers internal dns server) and check the performance graph for any error or drops b) check the dns section under floors column a blue tick indicates that the reachability to dns is fine steps a>hover the cursor on the graph and check for the availability > it should be true b>if the availability is false for a specific day or time it means that there was an outage detected nile portal availability graph 3\ check the nile portal (np) devices page → problem type → dns tile if red click on the dns tile to display the affected clientsclick on an affected client to troubleshoot a ‘client specific dns issue’ if green problem is likely a client issue and not a nile issue