NEWS FLASH - Cisco has released a new operating system for the new Nexus 7000 series switches: NX-OS. ;-)
NX-OS is based on the MDS series SAN-OS with a Cisco IOS CLI interface. NX-OS delivers a set of impressive software features all designed to provide 100% uptime and zero packet loss for traffic. Cisco understands we are entering, if not already in, a zero-defect world. Cisco is building products that operate in that manner.
As I mentioned, NX-OS is built on SAN-OS because of its inherent high-availability in SANs, but includes technologies from many areas. The Layer-3 routing code came from Cisco's aquisition of Procket several years ago. Procket was a startup focused on high-performance routing. It folded at the end of the boom and Cisco bought its technology and engineers, including Tony Li. The Layer-2 code came from Cisco's Catalyst team and the CLI is IOS.
The overriding goal of NX-OS is zero downtime. To achieve this lofty goal, NX-OS provides many features; some new and some already available in other Cisco (and competitor) operating systems.
NX-OS's In Service Software Upgrade (ISSU) provides the capability to perform transparent software upgrades on platforms with redundant supervisors, minimizing downtime and allowing customers to integrate the newest features and functions with little or no impact to network operation. Essentially, with dual supervisors that fail between each other without packet loss, a software upgrade can be done on one supervisor, a statefull switchover (SSO) occurs, and the second supervisor is upgraded. ISSU uses a Persistent Storage Service (PSS) to track the state of most processes and uses the standard-based graceful restart (NSF-GR) process for routing protocols. This can be done for major software upgrades or simple patches.
While in operation, NX-OS has process survivability. Process survivability ensures critical processes are run in protected memory space and independently from each other and the kernel. This provides granular service isolation and fault containment. So, if OSPF fails, it won't take down spanning-tree. Using NSF-GR, the OSPF process is restarted without needing to reboot the entire switch. All other processes run without impact.
For day-to-day management, Cisco included Generic Online Diagnostics (GOLD), Embedded Event Manager (EEM), Switch Port Analyzer (SPAN), Smart Call Home, and a XML API for device management. Plus, configuration verification and rollback is included. This has been around since IOS 12.3T, but was much too "new" for most networks (yes, part of JunOS). Having used this on JunOS, I can't tell you how nice that feature is.
NX-OS also removes "obsolete functions in order to harden the operating system". The thinking is to get rid of old features that no one uses anymore to reduce the possibilities of bugs. One of the technologies removed was PIM Dense Mode. I'm sure IPX isn't included either. ;-)
While all of these are very impressive, the pinnacle of new features is Virtual Device Contexts (VDCs). VDCs create logical switches out of a single physical switch. This is like VMware for Cisco. Not only does it mean separation of control, limited fault domains, and increased hardware capabilities, it also has radical effects on network design. I'll cover VDCs in a forthcoming blog, but, needless to say, it's an impressive technology.
The NX-OS software lifecycle seems similar to the SX-series for 7600s/6500s. There is a major release every 36 months (4.0, 5.0, 6.0, etc), feature releases every 6 months (4.1, 4.2, 4.3), and maintenance releases ever 4-6 weeks (4.1(1), 4.1(2), 4.1(3)). This is all tied into a general deployment, mature maintenance, and end-of-life program.
Overall, I'm impressed, especially with VDCs. I'd like these features availabile in all Cisco operating systems.
I have two problems with NX-OS. First, as I have mentioned before, it's another software line to manage. Yes, it may look like IOS, but it's not IOS. It has different features, bugs, versions, and supportability concerns. Many enterprises are looking at managing 4-5 types of Cisco software (IOS, IOS-modular, SAN-OS, NX-OS, and ASA/PIX); some six (for those with enough $$$s to get IOS-XR). This is just another software version to learn, understand, track, and test/verify.
Second, in grand Cisco tradition, there are three different types of NX-OS: Standard, Enterprise, and Advanced. IP Routing isn't even included with standard. That makes it look like a 3750 SMI. VDCs aren't included until you get to Advanced, so get ready to pay for the true power of the Nexus. NX-OS and the Nexus 7000 weren't expensive and complicated enough; let's try to ring some more money out of the product. I think Cisco was over thinking this part (marketing people). The Nexus 7000 is a core DC box. Trying to differentiate its use based on software feature sets is silly and petty.
Michael Morris is a communications team lead and network architect at a $3 billion high-tech company. His background is in enterprise WANs working with telcos, and developing large-scale routing designs. He has worked on networks at government and corporate organizations, including networks at two Fortune 10 companies. In his current role, he leads large-scale IT networking projects and develops and maintains architectural standards for data networks, storage area networks, IP Telephony, and security. Michael is a CCIE and has 11 years experience in networking and communications, including four years as a paratrooper in the U.S. Army. He has a bachelor's degree in MIS from the University at Buffalo. Recently, he was awarded the Network Professional Association® (NPA) Professional Excellence and Innovation Award for his work on network architecture, templates and enterprise MPLS design.
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Oh great. More Vista style
Oh great. More Vista style licensing. Couple that with the over six million lines of code and the linux kernel that powers NX-OS. Tell me how many people are going to line up to buy this...
Drink enough KoolAid and its like Modular IOS never happened.
If this wasn't intended tongue-in-cheek, I can only assume that you've not spent any appreciable amount of time using one of SAN-OS or IOS. Please clarify which so we can understand the perspective this is being written from.
Hardly. Instead, 15+ years of development has been kicked to the curb and we now get to deal with new bugs and implementation warts from top to bottom rather than continue to refine what exists.
...and when you can patch that process in response to a PSIRT issue, we'll be able to reuse even more Modular IOS presentations.
Short of VDC, which of these features didn't already exist in 12.2SX/SR? Yes, they're cool features, but they're not new and yet don't share the wide common base on implementations on an established Ethernet and IP routing platform.
Despite having similar names, these are not the same features (ie. SCH isn't even consistent as to whether its "call-home" or "callhome") and parroting press releasess suggesting that they are does the community disservice.
vlans provide virtualization
vlans provide virtualization at L2 and VRF provide the same at L3 in some low and high profile network routers and switches.
What VDC provide that we can't do now?
RE: vlans provide virtualization
I'll be doing a blog about this in the future, but VDCs virtualize almost everything in a switch, not just the Layer-2 domain (VLAN) or Layer-3 routing table (VRFs). VDCs create virtual switches running on a single kernel. Think of VMware for switches.
This is a powerful concept for network design, operations, and scalability.
Mike
Nexus 7000 doesn't do MPLS or MPLS VPN???
One issue I have with this box is that it will not do MPLS or MPLS VPN.
This means that, for those enterprises dipping their toes into VRF-lite/MPLS VPN use for creating Virtual Networks, this box is of far less use as a distribution switch or core switch.....
A gaping glaring hole in features in my opinion... large quanties of 10GE is nice, VDC is nice, but you have to have a PE and P router somewhere...
If you have a small MPLS network, P's and PE's are 6500+. The smaller medium/large enterprises building their own MPLS networks cannot justify the expense of GSR and CRS-1 core P and PE routers, they don't need the performance, but they do need the features.
It is LUDICROUS that a VDC or the "global" VDC/context in a Nexus 7000 switch, the new top-of-the-line switch, cannot perform as a PE or P router.
I would hope Cisco addresses this issue, particularly in light of the push towards Virtual Networks for segmentation. MPLS VPN is really the only viable way to extend logical network segmentation in a large network today.
Regards,
Sam