Network Service Issue Diagnosis

Problem

DNS, along with other network services/functions (e.g., LDAP, Authentication, etc.) are critical for users to access mission-critical applications. Today, many enterprises use distributed DNS systems to serve various user groups (on-premise, remote, etc.) for better load balancing and other operational efficiency. Users may be served by different DNS servers based on their locations and the time of the day. 

In such an enterprise’s main office, one local user group started to complain that an application (hosted in the enterprise’s main data center, see Fig. 2, below) was inaccessible or slow, so the enterprise’s IT staff had to determine if the problem is in the application or its components, or in the network, or in the network services which are invoked while accessing the application. Interestingly, the application was working fine for remote users and other user groups in the main office. Also, application owners (using APM tools) and network admins (using NPM tools) were saying everything was fine on their ends (based on their “siloed” views).  Now, the IT staff had to determine why the application was working fine for some users while being inaccessible for one user group in the main office when the performances of application servers and network resources were normal.

Solution

Ennetix xVisor was able to diagnose within minutes that the problem for the user group was their assigned DNS server. The network path to the DNS server was normal, but the DNS server was not resolving the queries from that specific user group properly (see Fig. 2). xVisor was able to pinpoint the problem location by using network service dependencies for a specific user group as it provided analytics-driven visibility of end-to-end application delivery paths, including mapping of the sliver of network resources the application depends on. The IT staff of the enterprise claimed that, without xVisor, this issue would take 24-48 hours to resolve, while xVisor diagnosed the issue in near real-time.