Administrator Guide
Table Of Contents
- Contents
- Figures
- Tables
- About This Document
- Understanding Fibre Channel Services
- Performing Basic Configuration Tasks
- Performing Advanced Configuration Tasks
- Routing Traffic
- Managing User Accounts
- Configuring Protocols
- Configuring Security Policies
- In this chapter
- ACL policies overview
- ACL policy management
- FCS policies
- DCC policies
- SCC policies
- Authentication policy for fabric elements
- IP Filter policy
- Creating an IP Filter policy
- Cloning an IP Filter policy
- Displaying an IP Filter policy
- Saving an IP Filter policy
- Activating an IP Filter policy
- Deleting an IP Filter policy
- IP Filter policy rules
- IP Filter policy enforcement
- Adding a rule to an IP Filter policy
- Deleting a rule to an IP Filter policy
- Aborting an IP Filter transaction
- IP Filter policy distribution
- Policy database distribution
- Management interface security
- Maintaining the Switch Configuration File
- Installing and Maintaining Firmware
- In this chapter
- Firmware download process overview
- Preparing for a firmware download
- Firmware download on switches
- Firmware download on an enterprise-class platform
- Firmware download from a USB device
- FIPS Support
- Test and restore firmware on switches
- Test and restore firmware on enterprise-class platforms
- Validating a firmware download
- Managing Virtual Fabrics
- In this chapter
- Virtual Fabrics overview
- Logical switch overview
- Logical fabric overview
- Management model for logical switches
- Account management and Virtual Fabrics
- Supported platforms for Virtual Fabrics
- Limitations and restrictions of Virtual Fabrics
- Enabling Virtual Fabrics mode
- Disabling Virtual Fabrics mode
- Configuring logical switches to use basic configuration values
- Creating a logical switch or base switch
- Executing a command in a different logical fabric context
- Deleting a logical switch
- Adding and removing ports on a logical switch
- Displaying logical switch configuration
- Changing the fabric ID of a logical switch
- Changing a logical switch to a base switch
- Setting up IP addresses for a Virtual Fabric
- Removing an IP address for a Virtual Fabric
- Configuring a logical switch to use XISLs
- Changing the context to a different logical fabric
- Creating a logical fabric using XISLs
- Administering Advanced Zoning
- In this chapter
- Special zones
- Zoning overview
- Broadcast zones
- Zone aliases
- Zone creation and maintenance
- Default zoning mode
- Zoning database size
- Zoning configurations
- Creating a zoning configuration
- Adding zones (members) to a zoning configuration
- Removing zones (members) from a zone configuration
- Enabling a zone configuration
- Disabling a zone configuration
- Deleting a zone configuration
- Clearing changes to a configuration
- Viewing all zone configuration information
- Viewing selected zone configuration information
- Viewing the configuration in the effective zone database
- Clearing all zone configurations
- Zone object maintenance
- Zoning configuration management
- Security and zoning
- Zone merging scenarios
- Traffic Isolation Zoning
- In this chapter
- Traffic Isolation Zoning overview
- Enhanced TI zones
- Traffic Isolation Zoning over FC routers
- General rules for TI zones
- Supported configurations for Traffic Isolation Zoning
- Limitations and restrictions of Traffic Isolation Zoning
- Admin Domain considerations for Traffic Isolation Zoning
- Virtual Fabric considerations for Traffic Isolation Zoning
- Traffic Isolation Zoning over FC routers with Virtual Fabrics
- Creating a TI zone
- Modifying TI zones
- Changing the state of a TI zone
- Deleting a TI zone
- Displaying TI zones
- Setting up TI over FCR (sample procedure)
- Administering NPIV
- Interoperability for Merged SANs
- In this chapter
- Interoperability overview
- Connectivity solutions
- Domain ID offset modes
- McDATA Fabric mode configuration restrictions
- McDATA Open Fabric mode configuration restrictions
- Interoperability support for logical switches
- Switch configurations for interoperability
- Zone management in interoperable fabrics
- Frame Redirection in interoperable fabrics
- Traffic Isolation zones in interoperable fabrics
- Brocade SANtegrity implementation in mixed fabric SANS
- E_Port authentication between Fabric OS and M-EOS switches
- FCR SANtegrity
- FICON implementation in a mixed fabric
- Fabric OS version change restrictions in an interoperable environment
- Coordinated Hot Code Load
- McDATA-aware features
- McDATA-unaware features
- Supported hardware in an interoperable environment
- Supported features in an interoperable environment
- Unsupported features in an interoperable environment
- Managing Administrative Domains
- In this chapter
- Administrative Domains overview
- Admin Domain management for physical fabric administrators
- Setting the default zoning mode for Admin Domains
- Creating an Admin Domain
- User assignments to Admin Domains
- Removing an Admin Domain from a user account
- Activating an Admin Domain
- Deactivating an Admin Domain
- Adding members to an existing Admin Domain
- Removing members from an Admin Domain
- Renaming an Admin Domain
- Deleting an Admin Domain
- Deleting all user-defined Admin Domains
- Deleting all user-defined Admin Domains non-disruptively
- Validating an Admin Domain member list
- SAN management with Admin Domains
- CLI commands in an AD context
- Executing a command in a different AD context
- Displaying an Admin Domain configuration
- Switching to a different Admin Domain context
- Admin Domain interactions with other Fabric OS features
- Admin Domains, zones, and zone databases
- Admin Domains and LSAN zones
- Configuration upload and download in an AD context
- Administering Licensing
- Monitoring Fabric Performance
- In this chapter
- Advanced Performance Monitoring overview
- End-to-end performance monitoring
- Frame monitoring
- ISL performance monitoring
- Top Talker monitors
- Adding a Top Talker monitor on an F_Port
- Adding Top Talker monitors on all switches in the fabric (fabric mode)
- Displaying the top n bandwidth-using flows on an F_Port
- Displaying top talking flows for a given domain ID (fabric mode)
- Deleting a Top Talker monitor on an F_Port
- Deleting the fabric mode Top Talker monitors
- Limitations of Top Talker monitors
- Trunk monitoring
- Displaying end-to-end and ISL monitor counters
- Clearing end-to-end and ISL monitor counters
- Saving and restoring monitor configurations
- Performance data collection
- Optimizing Fabric Behavior
- In this chapter
- Adaptive Networking overview
- Ingress Rate Limiting
- QoS: SID/DID traffic prioritization
- QoS zones
- QoS on E_Ports
- QoS over FC routers
- Virtual Fabric considerations for traffic prioritization
- High availability considerations for traffic prioritization
- Supported configurations for traffic prioritization
- Upgrade considerations for traffic prioritization
- Limitations and restrictions for traffic prioritization
- Setting traffic prioritization
- Setting traffic prioritization over FC routers
- Disabling QoS
- Bottleneck detection
- Supported configurations for bottleneck detection
- How bottlenecks are reported
- Limitations of bottleneck detection
- High availability considerations for bottleneck detection
- Upgrade and downgrade considerations for bottleneck detection
- Trunking considerations for bottleneck detection
- Virtual Fabrics considerations for bottleneck detection
- Access Gateway considerations for bottleneck detection
- Enabling bottleneck detection on a switch
- Excluding a port from bottleneck detection
- Displaying bottleneck detection configuration details
- Changing bottleneck alert parameters
- Displaying bottleneck statistics
- Disabling bottleneck detection on a switch
- Managing Trunking Connections
- Managing Long Distance Fabrics
- In this chapter
- Long distance fabrics overview
- Extended Fabrics device limitations
- Long distance link modes
- Configuring an extended ISL
- Buffer credit management
- Buffer-to-Buffer flow control
- Optimal buffer credit allocation
- Fibre Channel gigabit values reference definition
- Allocating buffer credits based on full-size frames
- Allocating buffer credits based on average-size frames
- Allocating buffer credits for F_Ports
- Displaying the remaining buffers in a port group
- Buffer credits for each switch model
- Maximum configurable distances for Extended Fabrics
- Buffer credit recovery
- Using the FC-FC Routing Service
- In this chapter
- FC-FC routing service overview
- Integrated Routing
- Fibre Channel routing concepts
- Setting up the FC-FC routing service
- Backbone fabric IDs
- FCIP tunnel configuration
- Inter-fabric link configuration
- FC Router port cost configuration
- EX_Port frame trunking configuration
- LSAN zone configuration
- Use of Admin Domains with LSAN zones and FCR
- Zone definition and naming
- LSAN zones and fabric-to-fabric communications
- Controlling device communication with the LSAN
- Setting the maximum LSAN count
- Configuring backbone fabrics for interconnectivity
- HA and downgrade considerations for LSAN zones
- LSAN zone policies using LSAN tagging
- LSAN zone binding
- Proxy PID configuration
- Fabric parameter considerations
- Inter-fabric broadcast frames
- Resource monitoring
- FC-FC Routing and Virtual Fabrics
- Upgrade and downgrade considerations for FC-FC routing
- Displaying the range of output ports connected to xlate domains
- M-EOS Migration Path to Fabric OS
- Inband Management
- Port Indexing
- FIPS Support
- Hexadecimal
- Index
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Buffer credit management
20
Buffer credit management
Buffer-to-buffer credit management affects performance over distances; therefore, allocating a
sufficient number of buffer credits for long-distance traffic is essential to performance. To prevent
a target device (either host or storage) from being overwhelmed with frames, the Fibre Channel
architecture provides flow control mechanisms based on a system of credits.
Each of these credits represents the ability of the device to accept additional frames. If a recipient
issues no credits to the sender, no frames can be sent. Pacing the transport of subsequent frames
on the basis of this credit system helps prevent the loss of frames and reduces the frequency of
entire Fibre Channel sequences needing to be retransmitted across the link.
Because the number of buffer credits available for use within each port group is limited,
configuring buffer credits for extended links may affect the performance of the other ports in the
group used for core-to-edge connections. You must balance the number of long-distance ISL
connections and core-to-edge ISL connections within a switch. Configuring long-distance ISLs
between core and edge switches is possible, but is not a recommended practice.
With the exception of 3xxx series and earlier switches, all switch ports provide protection against
buffer depletion through buffer limiting. A buffer-limited port reserves a minimum of eight buffer
credits, allowing the port to continue to operate rather than being disabled due to a lack of buffers.
The eight buffer minimum allows 4 and 8 Gbps speeds over distances within most data centers.
Buffer-limited operations are supported for the LS and LD extended ISL modes only. For LD,
distance in kilometers is the smaller of the distance measured during port initialization versus the
desired distance value. For LS, distance in kilometers is always the desired distance value.
Buffer-to-Buffer flow control
Buffer-to-Buffer (BB) credit flow control is implemented to limit the amount of data that a port may
send based on the number and size of the frames sent from that port. Buffer credits represent
finite physical port memory. Within a fabric, each port may have a different number of BB credits.
Within a connection, each side may have a different number of BB credits.
Buffer-to-Buffer flow control is flow control between adjacent ports in the I/O path, for example,
transmission control over individual network links. A separate, independent pool of credits is used
to manage Buffer-to-Buffer flow control. Buffer-to-Buffer flow control works by a sending port using
its available credit supply and waiting to have the credits replenished by the port on the opposite
end of the link. These BB credits are used by Class 2 and Class 3 service and rely on the Fibre
Channel Receiver-Ready (R_RDY) control word to be sent by the receiving link port to the sender.
The rate of frame transmission is regulated by the receiving port based on the availability of buffers
to hold received frames.
Upon arrival at a receiver, a frame goes through several steps. It is received, deserialized, decoded,
and is stored in a receive buffer where it is processed by the receiving port. If another frame arrives
while the receiver is processing the first frame, a second receive buffer is needed to hold this new
frame. Unless the receiver is capable of processing frames as fast as the transmitter is capable of
sending them, it is possible for all of the receive buffers to fill up with received frames. At this point,
if the transmitter should send another frame, the receiver will not have a receive buffer available
and the frame will be lost. Buffer-to-Buffer flow control provides consistent and reliable frame
delivery of information from sender to receiver.