PaloAlto Sessions Test

The Palo Alto firewall lets users to create sessions using different protocols such as Transmission Control Protocol (TCP), User Datagram Protocol (UDP), Internet Control Message Protocol (ICMP) or SSL Proxy connection. These communication protocols ensure reliability, end-to-end delivery and flow and error control of data during the user sessions.

Frequent overload condition on a firewall can actually cause irreversible damage to the firewall. If the Palo Alto Firewall is overloaded with sessions, it may actually slow down the request processing capability of the firewall. Under such circumstances, administrators will have to identify the type of sessions that are causing the overload – are they TCP sessions? UDP sessions? ICMP sessions? SSL Proxy sessions? – and investigate why the count of such sessions are unusually high on the firewall. Moreover it is the onus of the administrators to keep track of the session utilization as well. If the session utilization is high throughout, it may result in overload condition with the sessions hogging excessive network bandwidth. This may in turn cause slowdown of the firewall which when left unattended will lead to performance degradation. Administrators should therefore constantly monitor the sessions of the firewall and figure out what type of sessions are frequently causing overload. The PaloAlto Sessions test helps administrators in this regard.

This test monitors the sessions on the Palo Alto Firewall and reports the number of active TCP, UDP, ICMP and SSL Proxy sessions. In addition, this test reveals the overall session utilization and the SSL Proxy session utilization. This way, administrators can keep track of sudden spikes in the number of sessions and proactively be alerted to overload condition, if any.

Target of the test : A Palo Alto Firewall

Agent deploying the test : An external agent

Outputs of the test : One set of results for the firewall being monitored.

The figure below depicts the test configuration page of this test. Click on the parameters in the figure below to know what they are and how to configure them.

Configurable parameters for the test
Parameter Description

Test Period

How often should the test be executed.

Host

The IP address of the host for which this test is to be configured.

Port

Enter the port number at which the specified host listens to. By default, this is Null.

SNMPPort

The port at which the monitored target exposes its SNMP MIB; The default value is 161.

SNMPVersion

By default, the eG agent supports SNMP version 1. Accordingly, the default selection in the SNMPVersion list is v1. However, if a different SNMP framework is in use in your environment, say SNMP v2 or v3, then select the corresponding option from this list.

SNMPCommunity

The SNMP community name that the test uses to communicate with the firewall. This parameter is specific to SNMP v1 and v2 only. Therefore, if the SNMPVersion chosen is v3, then this parameter will not appear.

UserName

This parameter appears only when v3 is selected as the SNMPVersion. SNMP version 3 (SNMPv3) is an extensible SNMP Framework which supplements the SNMPv2 Framework, by additionally supporting message security, access control, and remote SNMP configuration capabilities. To extract performance statistics from the MIB using the highly secure SNMP v3 protocol, the eG agent has to be configured with the required access privileges – in other words, the eG agent should connect to the MIB using the credentials of a user with access permissions to be MIB. Therefore, specify the name of such a user against this parameter. 

Context

This parameter appears only when v3 is selected as the SNMPVersion. An SNMP context is a collection of management information accessible by an SNMP entity. An item of management information may exist in more than one context and an SNMP entity potentially has access to many contexts. A context is identified by the SNMPEngineID value of the entity hosting the management information (also called a contextEngineID) and a context name that identifies the specific context (also called a contextName). If the Username provided is associated with a context name, then the eG agent will be able to poll the MIB and collect metrics only if it is configured with the context name as well. In such cases therefore, specify the context name of the Username in the Context text box.  By default, this parameter is set to none.

AuthPass

Specify the password that corresponds to the above-mentioned Username. This parameter once again appears only if the SNMPVersion selected is v3.

Confirm Password

Confirm the AuthPass by retyping it here.

AuthType

This parameter too appears only if v3 is selected as the SNMPversion. From the Authtype list box, choose the authentication algorithm using which SNMP v3 converts the specified username and password into a 32-bit format to ensure security of SNMP transactions. You can choose between the following options:

  • MD5 – Message Digest Algorithm
  • SHA – Secure Hash Algorithm

EncryptFlag

This flag appears only when v3 is selected as the SNMPversion. By default, the eG agent does not encrypt SNMP requests. Accordingly, the this flag is set to No by default. To ensure that SNMP requests sent by the eG agent are encrypted, select the Yes option. 

EncryptType

If this EncryptFlag is set to Yes, then you will have to mention the encryption type by selecting an option from the EncryptType list. SNMP v3 supports the following encryption types:

  • DES – Data Encryption Standard
  • AES – Advanced Encryption Standard

EncryptPassword

Specify the encryption password here.

Confirm Password

Confirm the encryption password by retyping it here.

Timeout

Specify the duration (in seconds) within which the SNMP query executed by this test should time out in this text box. The default is 10 seconds.

Data Over TCP

By default, in an IT environment, all data transmission occurs over UDP. Some environments however, may be specifically configured to offload a fraction of the data traffic – for instance, certain types of data traffic or traffic pertaining to specific components – to other protocols like TCP, so as to prevent UDP overloads. In such environments, you can instruct the eG agent to conduct the SNMP data traffic related to the monitored target over TCP (and not UDP). For this, set this flag to Yes. By default, this flag is set to No.

Measurements made by the test
Measurement Description Measurement Unit Interpretation

Active sessions

Indicates the total number of sessions that are currently active on the firewall.

Number

This measure is a good indicators of session load on the firewall.

Active UDP sessions

Indicates the number of UDP sessions that are currently active on the firewall.

Number

A high value of this measure could indicate a UDP session overload on the firewall.

Active TCP sessions

Indicates the number of TCP sessions that are currently active on the firewall.

Number

A high value of this measure could indicate a TCP session overload on the firewall.

Active ICMP sessions

Indicates the number of ICMP sessions that are currently active on the firewall.

Number

A high value of this measure could indicate an ICMP session overload on the firewall.

Active SSL Proxy sessions

Indicates the number of SSL Proxy sessions that are currently active on the firewall.

Number

A high value of this measure could indicate SSL Proxy session overload on the firewall.

Session utilization

Indicates the utilization percentage of the sessions on the firewall.

Percentage

A high value for this measure indicates an overload condition on the firewall.

SSL Proxy session utilization

Indicates the utilization percentage of SSL Proxy sessions on the firewall.

Percentage

A high value for this measure could indicate an overload of the SSL Proxy sessions on the firewall.