opaque to the mirror service. Connections are made with standard UDP and TCP protocols, so Sun StorEdge 5310 NAS servers can be mirrored across any reachable network.

Since StorEdge File Replicator operates at the disk block level, the mirror system is an exact replica of the master system. However, since mirroring operations are not strictly real time, the mirror system may lag the master by a time delta dependent on the speed and quality of the network. While this network lag may prevent the mirror system from being an exact copy of the master at any given point, the integrity of the mirror system is guaranteed at all times. Only complete file system transactions are mirrored.

In the course of creating a duplicate volume, a mirror goes through three main phases: creation, replication, or sync, and sequencing. StorEdge File Replicator is a fault-tolerant technology. In all of the three main phases, the mirror handles errors with the intent of self-recovery as much as possible. When errors are encountered that are too severe for the mirror to handle on its own, it enters an ERROR state. In this state, user intervention is required to remedy the error and restart the mirror.

4.2.1Mirror Creation

There are several steps involved in the creation of a mirror. While the mirror is actually only created once, each step is revisited whenever the master system starts up after a reboot. As a general rule, when minor errors are encountered at any of those steps, the mirror enters a RESET state to wait a short time before re-attempting the failed step. More severe errors drive the mirror into the ERROR state, with the mirror status specifying the nature of the error.

When a mirror is started, it enters the NEW state. In this state, a buffer area is allocated within the mirror volume on the master system to store file system transactions while they are transferred to the mirror system. If enough free space cannot be found to accommodate the buffer, the mirror enters the ERROR state. If, as in the case of the reboot of a master system, the mirror buffer already exists, it is simply checked for validity.

Once the mirror buffer is created and/or validated, the mirror enters the INIT state. At this point, the master system attempts to establish a network connection to the mirror system via the NBD. If the mirror system cannot be reached at all, the mirror enters the ERROR state. If the mirror system can be reached, but there are errors encountered in setting up a connection, the mirror enters the RESET state. After a short wait, the mirror re-enters the INIT state and again attempts to establish a connection.

After a connection is set up between the master and mirror systems, the mirror enters the MAKEPARTS state. During this state, a replica of the volume on the master system is created on the mirror system. The volume on the mirror system is

4-10Sun StorEdge 5310 NAS Troubleshooting Guide • December 2004

Page 309 Page 311
Page 310
Image 310
Sun Microsystems 5310 NAS manual Mirror Creation
Page 309 Page 311

5310 NAS specifications

Sun Microsystems, known for its innovative computing solutions, launched the Sun 5310 Network Attached Storage (NAS) system, which marked a significant advancement in the realm of storage solutions in the early 2000s. The 5310 NAS was designed to provide high-performance, reliable, and scalable storage tailored for enterprise environments.

One of the standout features of the Sun 5310 NAS is its file-serving capabilities, which support multiple protocols, notably NFS (Network File System) and CIFS (Common Internet File System). This dual-protocol support allowed organizations to seamlessly integrate the NAS into diverse IT ecosystems, facilitating interoperability between UNIX, Linux, and Windows systems. The enhanced file-sharing capabilities made it an ideal solution for businesses with mixed operating environments.

The Sun 5310 NAS incorporates cutting-edge technologies to ensure high availability and data integrity. The system utilized a RAID (Redundant Array of Independent Disks) technology, providing various RAID levels to protect against data loss while optimizing performance. Additionally, the device featured hot-swappable drives, enabling maintenance and upgrades with minimal downtime, a crucial factor for business continuity.

Equipped with advanced management software, the Sun 5310 NAS offered users an intuitive interface for monitoring storage health and performance. This software included comprehensive reporting functionalities that allowed IT administrators to oversee usage patterns and capacity planning efficiently.

Scalability was another defining characteristic of the Sun 5310 NAS. The system could easily expand with additional storage modules, accommodating the growing needs of an organization without the necessity for complete system overhauls. This flexibility ensured that businesses could adapt their storage solutions to meet evolving data storage needs without incurring significant costs or disruptions.

In terms of performance, the Sun 5310 NAS featured high I/O throughput achieved through its robust hardware architecture and optimized file serving capabilities. This performance baseline was crucial for organizations that relied on heavy data workloads and required rapid access to information.

In summary, the Sun 5310 NAS from Sun Microsystems embodied a forward-thinking approach to network storage, blending reliability, scalability, and multi-protocol support. Its user-friendly management software, combined with the robustness of RAID technology and hot-swappable drives, made it a preferred choice for enterprises looking to streamline their storage infrastructure while safeguarding critical data.
Top Page Image Contents