DNOS or Dell Networking Operating System is a

network operating system A network operating system (NOS) is a specialized operating system for a network device such as a router, switch or firewall. Historically operating systems with networking capabilities were described as network operating systems, because they a ...

running on

switches In electrical engineering, a switch is an electrical component that can disconnect or connect the conducting path in an electrical circuit, interrupting the electric current or diverting it from one conductor to another. The most common type ...

from

Dell Networking Dell Networking is the new name for the networking portfolio of Dell. In the first half of 2013, Dell started to re-brand their different existing networking product brands to Dell Networking. Dell Networking will be the new name for the networkin ...

. It is derived from either the PowerConnect OS (DNOS 6.x) or Force10 OS/

FTOS FTOS or Force10 Operating System is the firmware family used on Force10 Ethernet switches. It has a similar functionality as Cisco's NX-OS or Juniper's Junos. FTOS 10 is running on Debian. As part of a re-branding strategy of Dell FTOS will be re ...

(DNOS 9.x) and will be made available for the 10G and faster Dell Networking S-series switches, the Z-series 40G core switches and DNOS6 is available for the N-series switches.

Two version families

The DNOS

family comes in a few main versions:

DNOS3

* DNOS 3.x: This is a family of firmware for the campus access switches that can only be managed using a web based GUI or run as unmanaged device.

DNOS6

* DNOS 6.x: This is the operating system running on the Dell Networking N-series (campus) networking switches. It is the latest version of the 'PowerConnect' operating system, running on a Linux Kernel. It is available as upgrade for the PowerConnect 8100 series switches (which then become a Dell Networking N40xx switch) and it also is installed on all DN N1000, N2000 and N3000 series switches. It has a full web-based GUI together with a full CLI (command line interface) and the CLI will be very similar to the original PowerConnect CLI, though with a range of new features like PVSTP (per VLAN spanning tree), Policy Based Routing and

MLAG A multi-chassis link aggregation group (MLAG or MC-LAG) is a type of link aggregation group (LAG) with constituent ports that terminate on separate chassis, primarily for the purpose of providing redundancy in the event one of the chassis fails ...

DNOS9

* DNOS 9.x: TeUTg on

NetBSD NetBSD is a free and open-source Unix operating system based on the Berkeley Software Distribution (BSD). It was the first open-source BSD descendant officially released after 386BSD was forked. It continues to be actively developed and is a ...

. Only the PowerConnect 8100 will be able to run on DNOS 6.x: all other PowerConnect ethernet switches will continue to run its own PowerConnect OS (on top of VxWorks) while the PowerConnect W-series run on a Dell specific version of ArubaOS. The Dell Networking S- xxxx and Z9x00 series will run on DNOS where the other Dell Networking switches will continue to run FTOS 8.x firmware.

OS10

OS10 is a Linux-based open networking OS that can run on all

Open Network Install Environment The Open Network Install Environment ( ONIE ) is an open-source "install environment", that acts as an enhanced boot loader utilizing facilities in a Linux/BusyBox environment. This small Linux operating system allows end-users and channel partne ...

(ONIE) switches. As it runs directly in a Linux environment network admins can highly automate the network platform and manage the switches in a similar way as the (Linux) servers.

Hardware Abstraction Layer

Three of the four product families from Dell Networking are using the

Broadcom Broadcom Inc. is an American designer, developer, manufacturer and global supplier of a wide range of semiconductor and infrastructure software products. Broadcom's product offerings serve the data center, networking, software, broadband, wirel ...

Trident+

ASIC An application-specific integrated circuit (ASIC ) is an integrated circuit (IC) chip customized for a particular use, rather than intended for general-purpose use, such as a chip designed to run in a digital voice recorder or a high-effici ...

s, but the company doesn't use the

API An application programming interface (API) is a way for two or more computer programs to communicate with each other. It is a type of software interface, offering a service to other pieces of software. A document or standard that describes how ...

s from

: the developers at Dell Networking have written their own

Hardware Abstraction Layer Hardware abstractions are sets of routines in software that provide programs with access to hardware resources through programming interfaces. The programming interface allows all devices in a particular class ''C'' of hardware devices to be acce ...

so that DNOS 9.x can run on different hardware platforms with minimal impact for the firmware. Currently three of the four DN switch families are based on the Broadcom Trident family (while the 4th - the E-series- run on self-developed ASICs); and two of them are running DNOS 9.x (S- and Z- series) and if the product developers want or need to use different hardware for new products they only need to develop a HAL for that new hardware and the same firmware can run on it. This keeps the company flexible and not dependent on a specific hardware-vendor and can use both 3rd party or self designed ASICs and chipsets. The underlying OS on which DNOS 9.x, runs, is based on

(while the DNOS 6.x runs on a Linux kernel), an implementation which is often used in embedded networking-systems. NetBSD is a very stable, open source, OS running on many different hardware platforms. By choosing for a proven technology with extended TCP functionality built into the core of the OS it reduces time during development of new products or extending the DNOS with new features.

Modular setup

DNOS 9.x is also modular where different parts of the OS run independently from each other within one switch: if one process would fail the impact on other processes on the switch are limited. This modular setup is also taken to the hardware level in some product-lines where a routing-module has three separate CPUs: one for management, one for L2 and one for L3 processing. This same approach is also used in the newer firmware-families from Cisco like the

NX-OS NX-OS is a network operating system for the Nexus-series Ethernet switches and MDS-series Fibre Channel storage area network switches made by Cisco Systems. It evolved from the Cisco operating system SAN-OS, originally developed for its MDS swi ...

for the Nexus product-line or the IOS XR for the high-end routers (the

Carrier Routing System Carrier Routing System (CRS) is a modular and distributed core router developed by Cisco Systems Inc that enables service providers to deliver data, voice, and video services over a scalable IP Next-Generation Network (NGN) infrastructure. In a ne ...

s) from

Cisco Cisco Systems, Inc., commonly known as Cisco, is an American-based multinational corporation, multinational digital communications technology conglomerate (company), conglomerate corporation headquartered in San Jose, California. Cisco develo ...

. (and unlike the original

IOS iOS (formerly iPhone OS) is a mobile operating system created and developed by Apple Inc. exclusively for its hardware. It is the operating system that powers many of the company's mobile devices, including the iPhone; the term also include ...

: processes under IOS aren't isolated from each other). This approach is regarded not only a way to make the firmware more resilient but also increases the security of the switches

Capabilities

All DNOS 9.x based switches offer a wide range of layer2 and layer3 protocols. All features are available on all switches: some switch models (in the S-series) offer an additional license for layer3 or routing: this additional license is NOT required to use that protocol, but only required to get support from the Dell Networking support department on using these features. All interfaces on DNOS 9.x running switches are configured as a layer3 interface and by default shutdown. To use such an interface as an ethernet switchport you need to configure it as such (with the command "switchport") and then enable that port using "no shutdown". Unlike DNOS 6.x (which provide web and CLI - with extensive API control via undocumented "dedug console" and "dev help" commands), DNOS 9.x only offers a documented command line interface (CLI) to configure and monitor the switch directly, though it is possible with the "Automation Tools" to create your own webGui on DNOS 9.x switches.

Layer2 capabilities

All standardized ethernet standards are supported by switches running FTOS including:

Spanning Tree Protocol The Spanning Tree Protocol (STP) is a network protocol that builds a loop-free logical topology for Ethernet networks. The basic function of STP is to prevent bridge loops and the broadcast radiation that results from them. Spanning tree also ...

and RSTP,

VLAN A virtual local area network (VLAN) is any broadcast domain that is partitioned and isolated in a computer network at the data link layer ( OSI layer 2).IEEE 802.1Q-2011, ''1.4 VLAN aims and benefits'' In this context, virtual, refers to a phys ...

and the

IEEE 802.1Q IEEE 802.1Q, often referred to as Dot1q, is the networking standard that supports virtual local area networking (VLANs) on an IEEE 802.3 Ethernet network. The standard defines a system of VLAN tagging for Ethernet frames and the accompanying proc ...

standards, QinQ or

IEEE 802.1ad IEEE 802.1ad is an Ethernet networking standard. It is as an amendment to IEEE standard IEEE 802.1Q-1998 and was incorporated into the base 802.1Q standard in 2011. The technique specified by the standard is known as provider bridging and stac ...

Link Layer Discovery Protocol The Link Layer Discovery Protocol (LLDP) is a vendor-neutral link layer protocol used by network devices for advertising their identity, capabilities, and neighbors on a local area network based on IEEE 802 technology, principally wired Ether ...

and LLDP MED. The S-series switches ending with a V and some of the E-series line-cards support

Power over Ethernet Power over Ethernet, or PoE, describes any of several standards or ad hoc systems that pass electric power along with data on twisted-pair Ethernet cabling. This allows a single cable to provide both data connection and electrical power to ...

or PoE with the standards for this protocol.

Layer3 capabilities

As mentioned above, by default an interface on a switch running DNOS 9.x are configured as a layer3 port. All these switches are thus routers with many interfaces that can (and most often are) reconfigured into a layer2 ethernet switch. All DNOS 9 switches run at least the following routing protocols:

Routing Information Protocol The Routing Information Protocol (RIP) is one of the oldest distance-vector routing protocols which employs the hop count as a routing metric. RIP prevents routing loops by implementing a limit on the number of hops allowed in a path from so ...

and RIP version 2,

OSPF Open Shortest Path First (OSPF) is a routing protocol for Internet Protocol (IP) networks. It uses a link state routing (LSR) algorithm and falls into the group of interior gateway protocols (IGPs), operating within a single autonomous syste ...

IS-IS Intermediate System to Intermediate System (IS-IS, also written ISIS) is a routing protocol designed to move information efficiently within a computer network, a group of physically connected computers or similar devices. It accomplishes this b ...

and

Border Gateway Protocol Border Gateway Protocol (BGP) is a standardized exterior gateway protocol designed to exchange routing and reachability information among autonomous systems (AS) on the Internet. BGP is classified as a path-vector routing protocol, and it mak ...

version 4.

Open Automation

Under the name OpenAutomation 2.0 Dell Networking switches running DNOS 9.x offers a number of features under this name. These features include:Dell Force10 Open Automation 2.0
visited 29 May 2013

Smart Scripting

Dell Networking switches support so called smart scripting. It is possible to develop scripts that run on the switches running DNOS 9. Both

Perl Perl is a family of two High-level programming language, high-level, General-purpose programming language, general-purpose, Interpreter (computing), interpreted, dynamic programming languages. "Perl" refers to Perl 5, but from 2000 to 2019 it ...

and Python are supported as scripting languages to automate environment specific repetitive tasks or to build in custom behavior. Users who write such scripts are promoted to share these scripts with the user-community and make them available to other Force10/DNOS users. Force10 introduced the smart scripting in FTOS in 2010, following other vendors like

for their

Nexus NEXUS is a joint Canada Border Services Agency and U.S. Customs and Border Protection-operated Trusted Traveler and expedited border control program designed for pre-approved, low-risk travelers. Members of the program can avoid waits at border ...

product range

Bare metal provisioning

Dell Networking switches support a ''bare metal provisioning'' option: if you need to deploy a number of similar switches you can put both (desired/latest) firmware release and standard user-specific configuration on a USB key: when deploying the switches you can insert the USB key, power-up the switch and it will automatically load the correct firmware and configuration. In combination with smart scripting someone can combine these features for a fully automated installation and configuration of new switches. It is also possible to run BMP via the network: unless re-configured to start in 'normal' mode all DNOS 9.x switches (and the earlier FTOS switches) will check if there is a BMP server on the network by sending out a DHCP/BOOTP request at boot: if it gets the correct response from the DHCP server (IP address, address of TFTP server and a script/config file name) it will contact a TFTP server to download correct firmware and configuration files and run that. You can disable this feature during initial configuration so that the switch will boot from the firmware and configuration saved on the switch NVRAM memory.

Virtual server networking

Part of the Open Automation platform are special features for the use of virtualisation in your datacenter. Virtualisation allows you to create complete (virtual) server-systems running on a standard hypervisor farm. This will create new challenges for networking in such a datacenter, support automated configuration of datacenter switches to connect newly created virtual servers. The open automation platform has several features to support this.Technical Whitepaper
Network automation with F10 Open Automation Framework
downloaded 25 May 2013

Network Automation

According to Dell the move to (server and datacenter) virtualisation is one of the most important developments in the IT industry. According to this vendor the industry must prevent that this path leads to getting locked-in into specific vendors due to the use of proprietary technologies. The open automation framework is an open framework that doesn't rely on proprietary solutions

Alternative OS

On some models Dell Networking switches (currently the S3048-ON, S4048-ON, S4810-ON, S6000-ON and Z9100) it is possible to run an alternative network OS: Cumulus Linux. This will run instead of DNOS on top of NetBSD. Cumulus Linux is a complete Linux distribution which uses the full TCP/IP stack of Linux.IT Online
Dell decouples hardware and software
7 February 2014. visited: 28 April 2014

References

{{Network operating systems Computer networking Dell Embedded operating systems Internet Protocol based network software Network operating systems