ExaGrid Statistics Test

ExaGrid supports data deduplication globally across all targets and all appliances in a scale-out system. Global deduplication ensures that all data is deduplicated regardless of the number of targets and/or the number of appliances in a system. In addition, global deduplication allows organizations the flexibility to redirect backup jobs to any target, on any appliance, at any time while maintaining data deduplication globally across the entire system.

Once the backup job is complete and off the network, the data is protected and immediately available to be restored. When deduplication and replication are complete, the data is ready for restore on the ExaGrid appliances at the disaster recovery site. The backup data is written directly from the backup server to ExaGrid’s disk landing zone at the highest possible rate with no inline processing to interfere, resulting in the shortest possible backup window.

As backup data is deduplicated, checksums are added to the deduplicated data as it is placed into the internal storage area, called the “repository.” These end-to-end checksums cover the deduplicated backup data itself, and are used to verify the backup data during processing and as it is read from disk. The deduplicated backup data can optionally be replicated to a remote site; these checksums are used to validate the replicated data as well.

If the backup data is not written to the disk at periodic intervals or if administrators notice a log in data reads/writes to the backup server , then, the whole purpose of deploying the backup server would be defeated! It is therefore, the onus of the administrators to overlook how well the backup data is written to / read from the respective disks. Also, administrators should constantly keep a vigil on the deduplication process that is carried out on the backup data. To aid administrators in this regard, eG Enterprise offers the ExaGrid Statistics test.

This test reports the overall performance of the target ExaGrid Backup Server in terms of how well backup data is written to the disk landing zone and read from the retention repository. In addition, administrators are alerted to performance lags if any, in the deduplication process. Using this test, administrators are also alerted to irregularities in backups.

Target of the test : ExaGrid Backup Server

Agent deploying the test : An external agent

Outputs of the test : One set of results for the target ExaGrid Backup Server being monitored

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.

SNMPPort

The port at which the monitored target exposes its SNMP MIB; the default 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
  • SHA224 - Secure Hash Algorithm 224 bit
  • SHA256 - Secure Hash Algorithm 256 bit
  • SHA384 - Secure Hash Algorithm 384 bit
  • SHA512 - Secure Hash Algorithm 512 bit

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 the 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
  • 3DES - Triple Data Encryption Standard
  • AES - Advanced Encryption Standard
  • AES128 - Advanced Encryption Standard 128 bit
  • AES192 - Advanced Encryption Standard 192 bit
  • AES256 - Advanced Encryption Standard 256 bit

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.

EngineID

This parameter appears only when v3 is selected as the SNMPVersion. Sometimes, the test may not report metrics when AES192 or AES256 is chosen as the Encryption type. To ensure that the test report metrics consistently, administrators need to set this flag to Yes. By default, this parameter is set to No.

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

Data reads

Indicates the rate at which data was read from the retention repository disk.

Mbps

Periodical tracking of these measures helps administrators in identifying irregularities/slowness in data reads/writes.

 

Data writes

Indicates the rate at which data was written to the disk landing zone.

Mbps

Deduplication rate

Indicates the rate at which data was deduplicated in the retention repository disk.

Mbps

Deduplication is the process of eliminating duplicate data, so as to increase the effective capacity in the disk tier, and the system’s RAM and flash tiers.

A high value is desired for this measure. A sudden/gradual decrease in the value of this measure is a cause of concern. Administrators are required to analyze the reason behind such issues and rectify them at the earliest so as to ensure that the deduplicated data is upto date.