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When Global Technical Support requests a connection to the TECH port of a physical XtremIO X2 XMS, the service machine should be connected to the MGMT ETH0 port on the server. This port is typically used for management purposes and allows for the necessary communication between the service machine and the XtremIO X2 XMS for technical operations and support.

References:

The Dell EMC support document outlines issues related to the management network configuration failure and mentions the physical XMS management port, which is relevant to the TECH port connection1.

Additional information on the XtremIO X2 system operation and management can be found in the “Introduction to XtremIO X2 Storage Array” document, which includes details on the XtremIO Management Server (XMS) and its ports2.

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For Microsoft Windows servers running MPIO, the optimal path selection policy when connected to an XtremIO cluster is Round Robin. This policy allows for load balancing across all available paths by distributing I/O evenly, which can lead to better performance and utilization of the storage resources.The Round Robin policy ensures that no single path is overloaded with I/O requests, which helps in maintaining consistent performance levels1.

References:

The Dell EMC SC Series: Microsoft Multipath IO Best Practices document provides insights into the recommended path selection policies for optimal performance2.

Additional information on MPIO and path selection policies can be found in the Dell EMC knowledge base articles1.

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The LUN queue depth setting per path in a customer’s environment configured with a dual X-Brick cluster, 8 ESXi hosts with 2 Emulex HBAs, each ESXi host having 8 LUNs, and each LUN visible through 4 paths, should be set to1281.

This is based on the best practice recommendation for Emulex HBAs in an XtremIO environment, as mentioned in the Dell Community1.The LUN queue depth on the Emulex HBA should be set to 1281.However, this setting might need to be adjusted based on the specific storage environment and the other storage arrays that are being used12.

In a VMware VDI solution utilizing VAAI XCOPY on XtremIO, the I/O size should be set to 256 kB.This setting is recommended to optimize the performance of the storage array during XCOPY operations, which are used to offload the copying of data within the storage array to the array itself, freeing up host resources1.

References:

The Dell support knowledge base article on using a VAAI claim rule to set the XCOPY size when using XtremIO for ESXi hosts recommends setting the XCOPY system value to 256 kB for XtremIO arrays1.

Additional information on VAAI XCOPY and its configuration can be found in the “Introduction to XtremIO X2 Storage Array” document, which provides insights into the system features that support such operations2.

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A response code of 400 in the context of RESTful API operations generally indicates that the request made by the client was malformed or contains a syntax error. This means that the data stream sent by the client to the server did not follow the rules as defined by the API specification.It could be due to various reasons such as incorrect request format, missing required parameters, or invalid parameter values1.

In the case of the Dell XtremIO environment, if a customer receives a 400 response code when attempting to create a volume via the RESTful API, it is likely due to a syntax error in the API command.The customer should review the API request to ensure that it conforms to the expected format and includes all necessary information as per the XtremIO API documentation2.

References:

Community discussions on the Dell Technologies website where similar issues have been addressed and the cause of the 400 error was identified as a syntax error in the RESTful API command2.

General information about the meaning of a 400 Bad Request error in REST APIs, which supports the conclusion that a syntax error is the cause1.

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When configuring the iSCSI SAN from the host to the XtremIO cluster, it is recommended to disable flow control features on the server, switches, and array ports.Flow control can cause a performance impact by serializing the flow for iSCSI ports, which is not desirable in high-performance storage solutions like XtremIO1. Disabling flow control ensures that the storage array operates without the limitations that flow control can impose, thus maintaining optimal performance.

References:

Dell EMC Switch Configuration Guide for iSCSI and Software-Defined Storage provides guidelines for the design and configuration of storage networks for iSCSI SAN, which includes recommendations on flow control settings2.

Community discussions on Dell Technologies website where it is mentioned that the latest best practices advise against enabling flow control for iSCSI with XtremIO, as it limits performance1.

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In a Dell XtremIO X2-R system, a four X-Brick cluster configuration includes two InfiniBand Switches1. Each InfiniBand Switch in a multi X-Brick system, such as the X2-R, is included to interconnect the X-Bricks within the cluster. While the specific number of ports is not directly stated in the search results, the configuration implies a high number of ports to support the connectivity between multiple X-Bricks. Based on the available information and typical configurations of such systems, it is reasonable to infer that each InfiniBand Switch would have 36 ports to provide the necessary interconnectivity for a four X-Brick cluster.

References:

The XtremIO X2 Specifications document provides details on system configurations and components, including InfiniBand Switches1.

Additional information on InfiniBand Switches and their role in multi X-Brick systems can be found in the XtremIO X2 Specification Sheet2.

In an XtremIO X2 cluster, the Disk Array Enclosure (DAE) chassis typically contains two Row Controllers. These Row Controllers are responsible for managing the operations of the SSDs within the DAE and ensuring data availability and integrity. The design of the DAE in an XtremIO X2 cluster is such that it provides a balance between performance, redundancy, and cost-effectiveness, with two Row Controllers being a common configuration for managing the SSDs effectively.

References:

The Dell XtremIO Design Achievement document provides information on the critical components of the XtremIO and X2 systems, including the DAE chassis and its controllers1.

Additional details on the architecture and components of the XtremIO X2 systems can be found in the Introduction to XtremIO X2 Storage Array white paper2.

ViPR SRM (Storage Resource Management) is the Dell EMC product that provides a comprehensive topology view from virtual or physical hosts down to the storage array volumes. This tool is designed to help customers manage complex virtualized environments by offering insights into application-to-storage dependencies.ViPR SRM delivers detailed reporting and analytics, which can be used to optimize storage performance and capacity planning1.

References:

The Introduction to XtremIO X2 Storage Array document provides information on the system features and management tools available for XtremIO arrays, which includes details on how ViPR SRM can be used to visualize and manage the storage infrastructure1.

Additional resources on the Dell EMC support site offer documentation and guides on how to effectively use ViPR SRM for storage resource management2.

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The Dell XtremIO X2 Storage Array uses an inline data deduplication process which involves fingerprinting data blocks. The fingerprinting process is a part of the data reduction technique that helps in identifying duplicate data blocks. When data enters the system, it is divided into small chunks, and each chunk is fingerprinted using a hashing algorithm. The size of the fingerprint is crucial as it determines the efficiency and accuracy of the deduplication process.

The specific bit size of the fingerprint created by the algorithm used by XtremIO is256 bits.This information is derived from the detailed descriptions of the system’s architecture and operation as provided in the Dell EMC XtremIO X2 Storage Array documentation1. The document outlines the system features, including inline data reduction techniques like deduplication and compression, which are essential components of XtremIO’s data management capabilities.

The 256-bit fingerprint size ensures a balance between deduplication efficiency and the probability of hash collisions (where different data blocks could result in the same fingerprint). A larger fingerprint size would reduce the chance of collisions but would require more storage space for metadata, while a smaller size would save metadata space but increase the risk of collisions. Therefore, the 256-bit size is a strategic choice for the XtremIO system’s deduplication process.

In summary, the fingerprint bit size for XtremIO’s deduplication algorithm is 256 bits, which is designed to optimize the system’s performance and data reduction capabilities while maintaining data integrity.