Sierra M244 Protocol Analyzer

Designed to address the next evolution of Serial Attached SCSI 4.0, the Sierra M244 is a four-port protocol analyzer that offers a built-in Jammer and exerciser for testing reliability and error recovery. With full support for 24Gb/s, 12Gfb/s, 6Gb/s and 3Gb/s SAS and SATA traffic, the Sierra M244 operating as an analyzer can record “4-wide” links. When licensed with the Infusion Jammer option, the M244 provides a “real-time” jammer capability to modify or corrupt traffic on 1, 2, or 4 ports simultaneously. The exerciser provides traffic generation and capture of packet level detail for debug and analysis.

The Sierra platforms feature a fully re-programmable protocol-processing engine that can adapt to changes in the specifications. Future SAS enhancements including “interleaved FEC” and “bit-level re-timers” can be addressed with a simple firmware update. Host connectivity to the Sierra is optimized for fast access to captured traffic and includes both SuperSpeed USB and Gigabit Ethernet. Mini-SAS HD ports allow easy connection to SAS 12 Gb/s as well as future SAS 24Gb/s devices.

Flexible licensing options allow support for dual-port (2) or wide-port (4) links. The M244 can be licensed to support SAS 4.0 or, alternatively, licensed with SAS 3.0 which is field-upgradeable to support 24G when needed. Memory buffers are shared across all active ports for maximum flexibility. High port count applications are possible (up to 32 physical links) by simply cascading multiple Sierra units together.

isconnect / Reconnect allows the Sierra system to be armed then disconnected from the host laptop. The analyzer will transparently wait for the trigger condition and preserve captured traffic in memory until the user reconnects to the analyzer. A built-in port provides DC power for target devices to supply SSDs or HDDs with 12v or 5v power. The rear chassis also provides a sync-port capable of synchronizing trace captures from multiple analyzer units, as well as from other protocols, using CrossSync technology.

Seamlessly integrated with Teledyne LeCroy’s expert analysis software, the Sierra platform overcomes the struggles of legacy debug tools with a revamped graphical interface featuring easy to understand displays of protocol traffic. For viewing commands and frames in sequential order, the Spreadsheet View provides a traditional table format that can be customized to add any field in a separate column. The Exchange level assembles frames and primitives into the logical SCSI commands, data and status transactions. This is critical for wide-port traces where large gaps can occur between command and status.

Use the Exchange View to see SCSI and SAS Management transactions fully decoded including Discovery request/responses, SCSI sense data and ASCQ fields. All of the analysis views can be used simultaneously and are automatically synchronized and displayed within one application. Any combination of display and filtering options can be configured as the default view making it faster to interpret captured traffic. Navigate traces at the logical command level, then easily drill-down to the chronological packet level.

The Sierra provides hardware triggering to pinpoint protocol events of interest. Trigger events can be specified at the lowest levels including error conditions, bus states, primitives (SOF, OPEN-REJECT, TRAIN-DONE, etc..), header fields (Tag, LBA, etc…) or payload patterns (CDB, Sense Data, etc…). Users can define sophisticated sequential event trigger scenarios including complex sequences such as timing intervals between events or errors at specific LBAs.

The Sierra SAS verification system provides extensive traffic metrics and statistics to help locate and identify protocol issues. Statistical reports provide hyperlinks to events in trace. Navigation in the Spreadsheet View is easy with Quick-Search. Click on any field and navigate forward or backward to the next occurrence. Add Boolean operators to find lower or higher values. Easily search by command, address, tag or status. The Quick Filter uses the same easy mechanism to hide selected fields. Markers can be added, searched and displayed as tooltips.

Building on the capabilities of the industry's first SAS/SATA error injection system, the InFusion™ option for Sierra M244 can programmatically alter or corrupt traffic for both SAS and SATA protocols. Fully integrated within the SAS4 Protocol Suite, InFusion is designed to create faulty link conditions while the analyzer records the real response from the system-under-test. The InFusion for SAS 4.0 is the ideal tool for stress testing systems while running real traffic and actual workloads.

The Sierra InFusion 24G option on the M244 platform can operate on up to four SAS or SATA links simultaneously. The M244 uses an active repeater front-end allowing it to programmatically alter or corrupt traffic for both SAS 24G and legacy speeds. The system can simultaneously record traffic over the same physical links selected for error injection. By default, the analyzer will use two channels to monitor before and after the error injection (A-J-A mode).

Once the Sierra InFusion system has been added to a SAS or SATA link, it automatically passes the boot up sequence and preserves all protocol handshaking between devices. It silently monitors the line while transmitting a faithful copy of the original data stream. The system will wait for a specific time interval or for an event designated by the user before it begins modifying frames or injecting errors. Sierra InFusion can be configured to send a single error, multiple errors, or random errors.

When changing fields within a frame, the Sierra InFusion traffic modifier will preserve the outbound frame structure, including recalculating the FEC and/or CRC if needed. The real response transmitted from the device-under-test will pass through the Sierra system, without modification to allow true end-to-end system testing.

Drop Frame	Drop Primitive	Capture DWORD
Drop Link	Replace Primitive	FEC Correctable error
Insert DWORDs	Change DWORDs	FEC UnCorrectable error
Truncate frame	Insert CRC-Error	Alter Speed Negotiation
Insert Running Disparity Error	Insert Symbol Error	Replace Data pattern
Insert Idle	Insert Primitive	Reject Connection
Corrupt Framing	Corrupt Flow control	Loop scenario
Corrupt SSP, SMP, STP frame contents	Insert Marker	Jump to any state
Force Check Condition	Count Event	Trigger

Sophisticated error injection strategies are possible using the dual sequencers with up to 256 sequential wait states per sequence. Each state can be configured to check for different conditions or inject different errors before branching to the next state. Looping allows the error injection sequence to repeat at specific intervals. Each sequential state can also include timers and counters to better isolate specific link conditions.

The exerciser connects to the system-under-test with standard MiniSAS HD cables and provides simultaneous traffic generation and capture of packet level detail for debug and analysis. It uses a script-based API that operates in real-time allowing users to meticulously test low-level functionality at full 24G line rate. It also allows users to transmit custom traffic patterns with low-level control of headers, payloads and timing. Invalid and marginal protocol conditions are easily generated to verify error recovery and device reliability.

Teledyne LeCroy's Sierra platforms provide the advanced features necessary to ease development and deployment of SAS and SATA solutions. With best-in-class features and an extensible design, the Sierra systems are is well suited for low-level silicon validation as well as system and software level protocol debug.