Practical Challenges in Scaling Networks First Intelligent Workshop May 19-21, 2003 Mark Bakke Cisco Systems
Cisco Networking 5428 Stackable iscsi-fc switch/gateway Small-medium business 9xxx Modular FC-based switch Enterprise iscsi Software Drivers Windows, Linux, Solaris, HPUX, AIX, iscsi Network Boot for Windows
Networks networks are here Better use of resources Centralized management Value is well-understood for larger systems Fibre Channel provides high performance Tens to hundreds of systems Network Management
Networks for the Masses iscsi enables storage networks for small systems Windows, Linux Ethernet provides an inexpensive (or free) interface Network boot makes servers smaller & cheaper Diskless blades contain fewer (or no) moving parts Power and cooling simpler Lower-cost blade servers increase density 14 to 20 servers per 3 rack units These will get smaller Thousands to tens of thousands of systems
Mom, can we keep it? All hosts connected to all storage But: Little networks turn into big networks Big networks have more to manage and hosts owned by different entities These may not agree on one big management scheme Network Management
Large Networks Many consumers Many providers Each has own: Access Protocols FC, iscsi, NAS Management Discovery Security These must interoperate Consumer Network SM Local Network Network SM Provider Consumer Network SM Local Network SM Provider
Access Points and Tiers Consumer Consumer App Network SM Network SM DB Local AP AP Local File Sys Network AP SM Network AP AP Network SM Provider Provider
Requirements To make storage networking a reality for most customers, they must be: Cheap Easy to manage and maintain Reliable and Available Secure Meet performance requirements
Problem Areas Access and Discovery can be Proxied Mostly just a matter of implementation Provisioning of Servers and No single management solution exists Current solutions don t close the loop Performance Latency and bottlenecks from access points & distance Security & Authentication Credentials not easy to manage Different for NAS, DB, Block storage
The User s Point of View The user cares about three things: The application runs and is available to users The application s data is safe The data is available to the application Ideally, nothing else matters Server hardware doesn t matter devices don t matter networks don t matter It s all just going to break anyway My Applications Other Stuff My Data
Someone has to Care IT must make sure: Applications have somewhere to run Application data is safe Applications can get to their data All of this meets user s performance needs The user doesn t see this happening Individually caring for 10,000 LUNs is not practical Need to set policies, and automate the rest
Server Provisioning must be separated from servers Network boot is an enabler for diskless servers Contain no moving parts Easy to replace Point new server at same disk and boot Or replicate application and stand by Easy to re-purpose Easy to replicate These could be done automatically
Provisioning Today 1. Application needs storage May be multiple tiers (NAS) 2. Set up LUN on disk array 3. Set up access list(s) for host 4. OR Set up an FC zone 5. Configure the host to access the storage 6. Repeat 10,000 times
Provisioning Next Step needs to be allocated: On-demand and automatically Based on application s requirements (SLA) Through multiple management environments also needs to grow automatically This requires cooperation with the application
Why not Tiered Networks? Most application networks use tiers Tiers mean bottlenecks Data paths are expensive Bottlenecks provide: Excellent Control Latency High Cost Multiple paths expensive Same goes for access points App DB File Sys
Flattening the Network Tiers collapse into one core network (IP) Direct storage access Redundancy cheaper Connectivity easier Performance better Users Users Apps Apps DB DB Network File File Access Points
Object-Based Flat Network Data access is direct (in most cases) Access points control-path only Tiers control-path only NAS DB Mirror Etc. Appearance is still hierarchical
Authentication & Authorization Essential to enable flat network Different permanent credentials for file, block, database, web Certificates & creds need to be easier to manage No standard protocols for use across SAN, NAS, web, etc. Temporary credentials for object access So we can revoke and expire them
Data Integrity Must be end-to-end File, DB, object, block could use same scheme & granularity OR do at app level Perhaps RDMA integration
Security Work to be Done Credentials need to be easier to manage Need to make certificate distribution and management easy Same infrastructure needs to be used by storage, NAS, other protocols to be effective Temporary credentials for object access End-to-end data integrity
Other Performance Issues copy how to do 10Gb+? Solution must work for blocks, objects, files RDMA can help solve this inexpensively Long-distance tape Tape emulation SSC-2
Summary Networking needs to Scale Requires flattening the physical network Requires more hierarchy logically Provisioning must be automated Need to evolve to objects or similar Need to solve credential/access problems Need to solve integrity/host bandwidth problems
Backup Slides
Access Points Provide access protocol conversion E.g. iscsi to Fibre Channel Provide discovery proxies Convert security and access control schemes Interface between management schemes Can be Database, File, or Object Servers Add latency