Category: Ethernet Data Storage

Intro to Incast, Head of Line Blocking, and Congestion Management

Tim Lustig
For a long time, the architecture and best practices of storage networks have been relatively well-understood. Recently, however, advanced capabilities have been added to storage that could have broader impacts on networks than we think. The three main storage network transports – Fibre Channel, Ethernet, and InfiniBand – all have mechanisms to handle increased traffic, but they are not all affected or implemented the same way. For instance, utilizing a protocol such as NVMe over Fabrics will offer very different methodologies for handling congestion avoidance, burst handling, and queue management when looking at one networking in comparison to another. Read More

The Impact of New Network Speeds on Storage

John Kim
In the last few years, Ethernet equipment vendors have announced big increases in line speeds, shipping 25, 50, and 100 Gigabits-per -second (Gb/s) speeds and announcing 200/400 Gb/s. At the same time Fibre Channel vendors have launched 32GFC, 64GFC and 128GFC technology while InfiniBand has reached 200Gb/s (called HDR) speed. But who exactly is asking for these faster new networking speeds, and how will they use them? Are there servers, storage, and applications that can make good use of them? How are these new speeds achieved? Are new types of signaling, cables and transceivers required? How will changes in PCIe standards and bandwidth keep up? And do the faster speeds come with different distance limitations? Read More

Everything You Wanted to Know about Memory

John Kim
Many followers (dare we say fans?) of the SNIA Networking Storage Forum (NSF) are familiar with our popular webcast series “Everything You Wanted To Know About Storage But Were Too Proud To Ask.” If you’ve missed any of the nine episodes we’ve done to date, they are all available on-demand and provide a 101 lesson on a range of storage related topics like buffers, storage controllers, iSCSI and more. Our next “Too Proud to Ask” webcast on May 16, 2019 will be “Everything You Wanted To Know About Storage But Were Too Proud To Ask – Part Taupe – The Memory Pod.” Traditionally, much of the IT infrastructure that we’ve built over the years can be divided fairly simply into storage (the place we save our persistent data), network (how we get access to the storage and get at our data) and compute (memory and CPU that crunches on the data). In fact, so successful has this model been that a trip to any cloud services provider allows you to order (and be billed for) exactly these three components. Read More

Scale-Out File Systems FAQ

John Kim
On February 28th, the SNIA Networking Storage Forum (NSF) took at look at what’s happening in Scale-Out File Systems. We discussed general principles, design considerations, challenges, benchmarks and more. If you missed the live webcast, it’s now available on-demand. We did not have time to answer all the questions we received at the live event, so here are answers to them all. Q. Can scale-out file systems do Erasure coding? A. Indeed, Erasure coding is a common method to improve resilience. Q. How does one address the problem of a specific disk going down? Where does scale-out architecture provide redundancy? A. Disk failures typically are covered by RAID software. Some of scale-out software also use multiple replicators to mitigate the impact of disk failures. Read More

What Are the Networking Requirements for HCI?

J Metz
Hyperconverged infrastructures (also known as “HCI”) are designed to be easy to set up and manage. All you need to do is add networking. In practice, the “add networking” part has been more difficult than most anticipated. That’s why the SNIA Networking Storage Forum (NSF) hosted a live webcast “The Networking Requirements for Hyperconverged Infrastructure” where we covered what HCI is, storage characteristics of HCI, and important networking considerations. If you missed it, it’s available on-demand. We had some interesting questions during the live webcast and as we promised during the live presentation, here are answers from our expert presenters: Read More

Experts Answer Virtualization and Storage Networking Questions

J Metz
The SNIA Networking Storage Forum (NSF) kicked off the New Year with a live webcast “Virtualization and Storage Networking Best Practices.” We guessed it would be popular and boy, were we right! Nearly 1,000 people registered to attend. If you missed out, it’s available on-demand. You can also download a copy of the webcast slides. Our experts, Jason Massae from VMware and Cody Hosterman from Pure Storage, did a great job sharing insights and lessons learned on best practices on configuration, troubleshooting and optimization. Here’s the blog we promised at the live event with answers to all the questions we received. Q. What is a fan-in ratio? A. fan-in ratio (sometimes also called an “oversubscription ratio”) refers to the number of hosts links related to the links to a storage device. Using a very simple example can help understand the principle: Say you have a Fibre Channel network (the actual speed or protocol does not matter for our purposes here). You have 60 hosts, each with a 4GFC link, going through a series of switches, connected to a storage device, just like in the diagram below: Read More

The Ins and Outs of a Scale-Out File System Architecture

John Kim
To meet the increasingly higher demand on both capacity and performance in large cluster computing environments, the storage subsystem has evolved toward a modular and scalable design. The scale-out file system has emerged as one implementation of the trend, in addition to scale-out object and block storage solutions. What are the key principles when architecting a scale-out file system? Find out on February 28th when the SNIA Networking Storage Forum (NSF) hosts The Scale-Out File System Architecture Overview, a live webcast where we will present an overview of scale-out file system architectures. This presentation will provide an introduction to scale-out-file systems and cover: Read More

Networking Questions for Ethernet Scale-Out Storage

Fred Zhang
Unlike traditional local or scale-up storage, scale-out storage imposes different and more intense workloads on the network. That’s why the SNIA Networking Storage Forum (NSF) hosted a live webcast “Networking Requirements for Ethernet Scale-Out Storage.” Our audience had some insightful questions. As promised, our experts are answering them in this blog. Q. How does scale-out flash storage impact Ethernet networking requirements? A. Scale-out flash storage demands higher bandwidth and lower latency than scale-out storage using hard drives. As noted in the webcast, it’s more likely to run into problems with TCP Incast and congestion, especially with older or slower switches. For this reason it’s more likely than scale-out HDD storage to benefit from higher bandwidth networks and modern datacenter Ethernet solutions–such as RDMA, congestion management, and QoS features. Read More

Virtualization and Storage Networking Best Practices from the Experts

J Metz
Ever make a mistake configuring a storage array or wonder if you’re maximizing the value of your virtualized environment? With all the different storage arrays and connectivity protocols available today, knowing best practices can help improve operational efficiency and ensure resilient operations. That’s why the SNIA Networking Storage Forum is kicking off 2019 with a live webcast “Virtualization and Storage Networking Best Practices.” In this webcast, Jason Massae from VMware and Cody Hosterman from Pure Storage will share insights and lessons learned as reported by VMware’s storage global services by discussing: Read More

RDMA for Persistent Memory over Fabrics – FAQ

John Kim
In our most recent SNIA Networking Storage Forum (NSF) webcast Extending RDMA for Persistent Memory over Fabrics, our expert speakers, Tony Hurson and Rob Davis outlined extensions to RDMA protocols that confirm persistence and additionally can order successive writes to different memories within the target system. Hundreds of people have seen the webcast and have given it a 4.8 rating on a scale of 1-5! If you missed, it you can watch it on-demand at your convenience. The webcast slides are also available for download. We had several interesting questions during the live event. Here are answers from our presenters:  Read More