eG Monitoring
 

Measures reported by CtxNsVpnVsTest

A vserver is a named NetScaler entity that external clients can use to access applications hosted on the servers. It is represented by an alphanumeric name, virtual IP address (VIP), port, and protocol. When a client attempts to access applications on a server, it sends a request to the VIP instead of the IP address of the physical server. When the NetScaler receives a request on the VIP, it terminates the connection at the vserver and uses its own connection with the server on behalf of the client. The port and protocol settings of the vserver determine the applications that the vserver represents.

vservers can be grouped into various categories. One such vserver is the virtual private network (VPN) virtual server. This server decrypts tunneled traffic and sends it to intranet applications. To understand the workload of each of these VPN virtual servers and isolate overloaded servers, use the NS VPN Virtual Servers test.

The measures made by this test are as follows:

Measurement Description Measurement Unit Interpretation
Server_state Indicates the current state of this virtual server.   If the virtual server is up, then the value of this measure is Up. If the virtual server is down, then the value of this measure is Down. The numeric values that correspond to these measure values have been listed in the table below:

Measure Value Numeric Value
Up 0
Down 1
Out of service 2
Transition out of service 3
Down when going out of service 4
Unknown -1

Note:

By default, this measure reports the above-mentioned Measure Values while indicating whether a virtual server is up/down. However, in the graph of this measure, the Measure Values will be represented using their corresponding numeric equivalents only.

Use the detailed diagnosis of this measure to determine the primary IP address, primary port, and protocol type of each VPN virtual server being monitored.

Req_data_received Indicates the amount of request data received by this virtual server during the last measurement period. MB These are good measures of the request and response load on a virtual server. By comparing the value of each of these measures across virtual servers, you can instantly identify overloaded servers.
Res_data_received Indicates the amount of response data received by this virtual server during the last measurement period. MB
Req_received Indicates the number of requests received by this virtual server during the last measurement period. Number
Res_received Indicates the number of responses received by this virtual server during the last measurement period. Number
Current_users Indicates the number of users who are currently logged into this virtual server. Number A high value is indicative of high user load on the virtual server. By continuously tracking changes to this measure alongside the value of the Max_users measure, you can figure out when this upper threshold (i.e., Max_users measure) is likely to be reached/crossed.
Max_users Indicates the number of concurrent users who are allowed to login to this virtual server. Number  
Curr_tot_users Indicates the total number of users connected to this virtual server. Number This measure is a good indicator of total workload on the virtual server. Compare the value of this measure across the virtual servers to know which virtual server is overloaded.
Up_servers Indicates the number of STA severs, which are bound to this virtual server, that are currently up and running. Number The Secure Ticket Authority (STA) is responsible for issuing session tickets in response to connection requests for published applications on XenApp and published desktops on XenDesktop. These session tickets form the basis of authentication and authorization for access to published resources. If users have valid STA tickets, the gateway assumes that they passed the authentication checks and should be permitted access.

A STA server can be bound globally or to virtual servers. You can also add multiple servers running the STA when a virtual server is configured.

The value of this measure is should be high. A low value for this measure may indicate that the most of the STA servers are not running which may lead to security issues while connecting to the NetScaler.
Down_servers Indicates the number of STA severs that are currently down. Number The value of this measure should be zero. A non-zero value for this measure is a cause for concern.
Pct_of_up_servers Indicates the percentage of STA severs that are currently up and running. Percent