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• AIX

lscfg –v –l fcs#
(fcs – FC Adapter)
SMIT

• HP-UX

fcmsutil /dev/td#
(td – TACHYON Adapter)
SAM

• WIN:

emulexcfg –emc or
hbanywhere
I can use Storage Explorer to see DETAILED INFORMATION about the Fibre CHANNEL host bus adapters (HBAs).

• Solaris

/usr/sbin/lpfc/lputil
Also I can use:
more /var/adm/messages | grep –i wwn |more dmesg

• VMware vSphere ESX/ESXi host

There are several ways to get HBA WWNs on VM
vSphere Client;
Using ESXi Shell;
Using Powershell / PowerCLI script.

• LINUX

/sys/class/scsi_host/hostN/device/fc_host/hostN/port_name
Where “N” is the number of device for your fibre HBAs

lscfg –v –l fcs#
(fcs – FC Adapter)
SMIT

fcmsutil /dev/td#
(td – Tachyon Adapter)
SAM

emulexcfg –emc or
hbanywhere
I can use Storage Explorer to see detailed information about the Fibre Channel host bus adapters (HBAs).

/usr/sbin/lpfc/lputil
Also I can use:
more /var/adm/messages | grep –i wwn |more dmesg

There are several ways to get HBA WWNs on VM
vSphere Client;
Using ESXi Shell;
Using Powershell / PowerCLI script.

/sys/class/scsi_host/hostN/device/fc_host/hostN/port_name
Where “N” is the number of device for your fibre HBAs

• Plan
• Validation with Support Matrix for Host CONNECTIVITY
• PROVIDE Connectivity
• Pick Volumes
• MAKE Meta Volumes if necessary
• Map out Zoning
• Map to STORAGE arrays PORTS
• Create Zones
• LUN Mask
• Discover on Server

USE FIXED, or Preferred, path MANAGEMENT policy to INTELLIGENTLY segment workload across both CONTROLLERS.

Use Fixed, or Preferred, path management policy to intelligently segment workload across both controllers.

• Servers/ hosts uses multipathing for failover from one path to the other when one path from the Servers/host to the SAN becomes unavailable, the host SWITCHES to another path.
• Servers/ hosts can also use multipathing for load balancing.

Types of policy:

• Most RECENTLY Used: The path used by a LUN is not be altered unless an event instructs the path to change. I will use this policy is for Active/Passive arrays and many pseudo active/active arrays. Most recently used (mru) selects the path most recently used to send I/O to a device.
• Fixed: The path used by a LUN is ALWAYS the one marked as preferred, unless that path is unavailable I use this policy is for Active/Active arrays. Fixed (fixed) uses only the active path.
• Round ROBIN: Round robin (rr) uses the mru target selection policy and the any HBA selection policy to SELECT paths.
• Custom (custom) sets the LUN to expect a custom policy.

Types of policy:

• Input/output operations per second (IOPS) is the measure of how MANY input/output operations a storage device can COMPLETE within one second.
• IOPS is important for transaction-based applications.
• IOPS performance is heavily dependent on the number and type of disk drives.

To calculate IOPS of a HARD disk drive:

1

IOPS = —————————————

(Average Latency) + (Average Seek Time)

To calculate IOPS in a RAID:

(TOTAL Workload IOPS * Percentage of workload that is read operations) + (Total Workload IOPS * Percentage of workload that is read operations * RAID IO Penalty)

To calculate IOPS of a Hard disk drive:

1

IOPS = —————————————

(Average Latency) + (Average Seek Time)

To calculate IOPS in a RAID:

(Total Workload IOPS * Percentage of workload that is read operations) + (Total Workload IOPS * Percentage of workload that is read operations * RAID IO Penalty)

Use the formula:

Total Approximate Drives REQUIRED = (RAID Group IOPS / (Hard DRIVE Type IOPS)) + Large Random I/O adjustment + Hot SPARES + System Drives.

Use the formula:

Total Approximate Drives required = (RAID Group IOPS / (Hard Drive Type IOPS)) + Large Random I/O adjustment + Hot Spares + System Drives.

Capacity = Heads X CYLINDERS X SECTORS X Block SIZE

Capacity = Heads X Cylinders X Sectors X Block Size

Capacity = HEADS X Cylinders X SECTORS X Block Size

Capacity = Heads X Cylinders X Sectors X Block Size

Total APPROXIMATE Drives = (RAID Group IOPS / (Hard DRIVE TYPE IOPS)) + Large Random I/O ADJUSTMENT + Hot Spares + System Drives

Total Approximate Drives = (RAID Group IOPS / (Hard Drive Type IOPS)) + Large Random I/O adjustment + Hot Spares + System Drives

Total Approximate Drives REQUIRED = (RAID GROUP IOPS / (Hard DRIVE Type IOPS)) + Large RANDOM I/O adjustment + Hot Spares + System Drives

Total Approximate Drives required = (RAID Group IOPS / (Hard Drive Type IOPS)) + Large Random I/O adjustment + Hot Spares + System Drives

Calculation of the maximum queue DEPTH: The queue depth is the number of I/O operations that can be RUN in PARALLEL on a device.

Calculation of the maximum queue depth: The queue depth is the number of I/O operations that can be run in parallel on a device.

The queue depth is the maximum NUMBER of COMMANDS that can be QUEUED on the system at the same time.

The queue depth is the maximum number of commands that can be queued on the system at the same time.

Max IOPS an HBA PORT can generate to any LUN = (Device Queue DEPTH per LUN * (1 / (STORAGE LATENCY in ms/1000)))

Max IOPS an HBA Port can generate to any LUN = (Device Queue Depth per LUN * (1 / (Storage Latency in ms/1000)))

I will check the OS log files/EVENT logs for errors:

AIX: errpt -a
Windows: event logs
Solaris: /var/adm/messages
linux: /var/log/messages
HPUX: /var/adm/syslog/syslog.log
Tru64: /var/adm/syslog
SGI IRIX: /var/adm/SYSLOG
ESX: /var/log/vmkernel
ESXi: /var/log/messages

I will check the OS log files/event logs for errors:

AIX: errpt -a
Windows: event logs
Solaris: /var/adm/messages
linux: /var/log/messages
HPUX: /var/adm/syslog/syslog.log
Tru64: /var/adm/syslog
SGI Irix: /var/adm/SYSLOG
ESX: /var/log/vmkernel
ESXi: /var/log/messages

YES. I have been using Brocade Fabric and I have used “support save “to collect various logs for any issues.

Syntax:

supportsave [ os | platform | l2 | l3 | custom | core | all ] <TFTP SERVER IP> <RELATIVE path> <user_tag>

Yes. I have been using Brocade Fabric and I have used “support save “to collect various logs for any issues.

Syntax:

supportsave [ os | platform | l2 | l3 | custom | core | all ] <tftp server IP> <relative path> <user_tag>

Buffer credits, also called buffer-to-buffer credits (BBC) are used as a flow control method by Fibre Channel technology and represent the number of frames a PORT can store. Fibre Channel interfaces use buffer credits to ensure all PACKETS are delivered to their destination. Flow-control mechanism to ensure that Fibre Channel switches do not run out of BUFFERS, so that switches do not drop frames .overall performance can be boosted by optimizing the buffer-to-buffer credit ALLOTTED to each port.

Buffer credits, also called buffer-to-buffer credits (BBC) are used as a flow control method by Fibre Channel technology and represent the number of frames a port can store. Fibre Channel interfaces use buffer credits to ensure all packets are delivered to their destination. Flow-control mechanism to ensure that Fibre Channel switches do not run out of buffers, so that switches do not drop frames .overall performance can be boosted by optimizing the buffer-to-buffer credit allotted to each port.

Number of BUFFERS: BB_Credit = [port speed] X [ROUND trip TIME] / [frame SIZE]

Number of Buffers: BB_Credit = [port speed] x [round trip time] / [frame size]

I have used Brocade SAN and it has these load balancing policies:

• DLS – Dynamic Load Sharing. FSPF link balancing by FSPF routing protocol
• DPS – Dynamic Path Selection by effectively striping IOs at SCSI LEVEL
• Frame-level load balancing – Each successive frame on a different PHYSICAL ISL.

I have used Brocade SAN and it has these load balancing policies:

• I will directly connect PARTICIPATING switches byInter-Switch Link (ISL) cables.
• I will KEEP the TRUNK ports in the same port group
• I will MAKE sure Trunk ports run at the same speed
• I will ENSURE that all Trunk ports are set to the same ISL mode (L0 is the default).
• I will convert Trunk ports to be E_Ports or EX_Ports

use: Fan Out

For EXAMPLE 10:1.

I will determine this RATIO, based on the server platform and PERFORMANCE REQUIREMENT by CONSULTING Storage vendors

use: Fan Out

For example 10:1.

I will determine this ratio, based on the server platform and performance requirement by consulting Storage vendors

Drooping= BANDWIDTH INEFFICIENCY

Drooping begins if: BB_Credit&LT;RTT/SF

Where RTT = Round Trip TIME

SF = Serialization delay for a data frame

Drooping= Bandwidth Inefficiency

Drooping begins if: BB_Credit<RTT/SF

Where RTT = Round Trip Time

SF = Serialization delay for a data frame

• ISL over SUBSCRIPTION Ratio
• SAN Fan–in and Fan-Out
• Storage PORTS
• Server I/O Profiles
• Fabric FEATURES
• Continuity REQUIREMENTS

Design should address three separate levels:

1. Tier 1: 99.999% availability (5 MINUTES of downtime per year)
2. Tier 2: 99.9% availability (8.8 hours average downtime per year, 13.1 hours maximum)
3. Tier 3: 99% availability (3.7 days of downtime per year)

Design should address three separate levels:

SAN Storage array has data integrity built into it.

A storage array uses spae disk drives to take the place of any disk drives that are blocked because of errors. Hot spares are available and will spare out predictively when a drive fails.

There are TWO types of disk sparing:

Dynamic Sparing: Data from the failed or blocked drive is copied directly to the new spare drive from the FAILING drive

Correction Copy: Data is regenerated from the remaining good drives in the parity GROUP. For RAID 6, RAID 5, and RAID 1, after a failed disk has been replaced, the data is copied back to its ORIGINAL LOCATION, and the spare disk is then available.

SAN Storage array has data integrity built into it.

A storage array uses spae disk drives to take the place of any disk drives that are blocked because of errors. Hot spares are available and will spare out predictively when a drive fails.

There are two types of disk sparing:

Dynamic Sparing: Data from the failed or blocked drive is copied directly to the new spare drive from the failing drive

Correction Copy: Data is regenerated from the remaining good drives in the parity group. For RAID 6, RAID 5, and RAID 1, after a failed disk has been replaced, the data is copied back to its original location, and the spare disk is then available.

Use GPT.

GUID Partition Table, GPT is a part of the EFI standard that defines the layout of the partition table on a hard drive. GPT PROVIDES redundancy by WRITING the GPT header and partition table at the beginning of the disk and also at the end of the disk.

GPT Uses 64-bit LBA for storing Sector NUMBERS. GPT disk can theoretically support up to 2^64 LBAs. Assuming 512 byte sector emulation, maximum capacity of a GPT disk = 9.4 x 10^21 bytes = 9.4 zettabytes (ZB)

Use GPT.

GUID Partition Table, GPT is a part of the EFI standard that defines the layout of the partition table on a hard drive. GPT provides redundancy by writing the GPT header and partition table at the beginning of the disk and also at the end of the disk.

GPT Uses 64-bit LBA for storing Sector numbers. GPT disk can theoretically support up to 2^64 LBAs. Assuming 512 byte sector emulation, maximum capacity of a GPT disk = 9.4 x 10^21 bytes = 9.4 zettabytes (ZB)

To CALCULATE IOPS per drive the formula I will use is:

1000 / (SEEK Time + LATENCY) = IOPS

To calculate IOPS per drive the formula I will use is:

1000 / (Seek Time + Latency) = IOPS

SSD DRIVES have no MOVABLE PARTS and therefore have no RPM.

SSD drives have no movable parts and therefore have no RPM.

The required Bandwidth=the required bandwidth is DETERMINED by MEASURING the average number of WRITE OPERATIONS and the average SIZE of write operations over a period of time.

The required Bandwidth=the required bandwidth is determined by measuring the average number of write operations and the average size of write operations over a period of time.

RAW CAPACITY= USABLE + PARITY

Raw Capacity= Usable + Parity

Select it on the basis of transmission distance.

If the distance is less than a couple of MILES, I will USE MULTIMODE fibre cable.

If the distance is more than 3-5 miles, I will use SINGLE mode fibre cable.

Select it on the basis of transmission distance.

If the distance is less than a couple of miles, I will use multimode fibre cable.

If the distance is more than 3-5 miles, I will use single mode fibre cable.

The device masking commands ALLOW you to:

Assign and mask access privileges of hosts and adapters

CONNECTED in a Fibre Channel TOPOLOGY to storage arrays and devices.

Specify the host bus adapters (HBAs) through which a host can access storage arrays devices.

Display or list device masking objects and their RELATIONSHIPS: Typical objects are hosts, HBAs, storage arrays devices, and Fibre Channel Adapter (FA) ports.

Modify properties, such as names and access privileges associated with device masking objects (for example, CHANGE the Name of a host).

The device masking commands allow you to:

Assign and mask access privileges of hosts and adapters

Connected in a Fibre Channel topology to storage arrays and devices.

Specify the host bus adapters (HBAs) through which a host can access storage arrays devices.

Display or list device masking objects and their relationships: Typical objects are hosts, HBAs, storage arrays devices, and Fibre Channel Adapter (FA) ports.

Modify properties, such as names and access privileges associated with device masking objects (for example, change the Name of a host).

• Hard zoning is zoning which is implemented in HARDWARE.
• Soft zoning is zoning which is implemented in software.
• Hard zoning physically blocks ACCESS to a zone from any device outside of the zone.
• Soft zoning uses filtering implemented in fibre channel switches to PREVENT ports from being seen from outside of their assigned zones. The security VULNERABILITY in soft zoning is that the ports are still accessible if the user in another zone correctly guesses the fibre channel address.

Port zoning utilizes physical ports to DEFINE security zones. A USER’s access to data is determined by what physical port he or she is connected to. With port zoning, zone information must be updated every time a user changes switch ports. In addition, port zoning does not allow zones to overlap. Port zoning is normally IMPLEMENTED using HARD zoning, but could also be implemented using SOFT zoning.

Port zoning utilizes physical ports to define security zones. A user’s access to data is determined by what physical port he or she is connected to. With port zoning, zone information must be updated every time a user changes switch ports. In addition, port zoning does not allow zones to overlap. Port zoning is normally implemented using hard zoning, but could also be implemented using soft zoning.

WWN zoning uses name servers in the switches to EITHER allow or block access to PARTICULAR World Wide Names (WWNs) in the fabric. A major advantage of WWN zoning is the ability to recable the fabric without having to redo the ZONE information. WWN zoning is susceptible to unauthorized access, as the zone can be BYPASSED if an attacker is able to spoof the World Wide Name of an authorized HBA.

WWN zoning uses name servers in the switches to either allow or block access to particular World Wide Names (WWNs) in the fabric. A major advantage of WWN zoning is the ability to recable the fabric without having to redo the zone information. WWN zoning is susceptible to unauthorized access, as the zone can be bypassed if an attacker is able to spoof the World Wide Name of an authorized HBA.

LOGICAL Unit Number or LUN is a logical REFERENCE to entire physical disk, or a subset of a larger physical disk or disk volume or portion of a STORAGE subsystem.

Logical Unit Number or LUN is a logical reference to entire physical disk, or a subset of a larger physical disk or disk volume or portion of a storage subsystem.

• Use the Persistent Binding for Tape DEVICES.
• Persistent binding is a HOST-centric enforced way of directing an operating system to assign certain SCSI target IDs and LUNs.
• Persistent Name Binding support is for target devices.
• Persistent binding is provided for users to associate a SPECIFIED device World Wide Port Name (WWPN) to a specified SCSI target ID.
• For example, where a specific host will always assign SCSI ID 3 to the first router it FINDS, and LUNs 0, 1, and 2 to the three-tape drives attached to the router.

Practical examples:

For Emulex HBA on a Solaris host for setting up persistent binding:

# lputil
MAIN MENU

1. List Adapters
2. Adapter Information
3. Firmware Maintenance
4. Reset Adapter
5. Persistent Bindings

Using option 5 will perform a manual persistent binding and the file is: /kernel/drv/lpfc.conf file.

lpfc.conf file looks like:

fcp-bind-WWNN=”50060XY484411 c6c11:lpfc0t1″,
“50060XY4411 c6c12:lpfc1t2”;

sd.conf file looks like:
name=”sd” parent=”lpfc” target=1 lun=0;
name=”sd” parent=”lpfc” target=2 lun=0;

Reconfigure:

# touch /reconfigure
# shutdown -y -g0 -i6

Practical examples:

For Emulex HBA on a Solaris host for setting up persistent binding:

# lputil
MAIN MENU

Using option 5 will perform a manual persistent binding and the file is: /kernel/drv/lpfc.conf file.

lpfc.conf file looks like:

fcp-bind-WWNN=”50060XY484411 c6c11:lpfc0t1″,
“50060XY4411 c6c12:lpfc1t2”;

sd.conf file looks like:
name=”sd” parent=”lpfc” target=1 lun=0;
name=”sd” parent=”lpfc” target=2 lun=0;

Reconfigure:

# touch /reconfigure
# shutdown -y -g0 -i6

LUN Masking is important because Windows based SERVERS attempt to WRITE volume labels to all available LUN’s. This can render the LUN’s UNUSABLE by other operating systems and can result in data loss.

Device masking lets you CONTROL your host HBA access to certain storage arrays devices. A device masking database, based in the storage arrays unit, eliminates conflicts through centralized monitoring and access records. Both HBA and storage arrays director ports in their Channel topology are uniquely identified by a 64-bit World Wide Name (WWN). For ease of use, you can associate an ASCII World Wide Name (AWWN) with each WWN.

LUN Masking is important because Windows based servers attempt to write volume labels to all available LUN’s. This can render the LUN’s unusable by other operating systems and can result in data loss.

Device masking lets you control your host HBA access to certain storage arrays devices. A device masking database, based in the storage arrays unit, eliminates conflicts through centralized monitoring and access records. Both HBA and storage arrays director ports in their Channel topology are uniquely identified by a 64-bit World Wide Name (WWN). For ease of use, you can associate an ASCII World Wide Name (AWWN) with each WWN.

LUN (Logical Unit Number) Masking is an AUTHORIZATION process that makes a LUN AVAILABLE to some HOSTS and unavailable to other hosts.

LUN Masking is implemented primarily at the HBA (Host Bus Adapter) level. LUN Masking implemented at this level is VULNERABLE to any ATTACK that compromises the HBA. Some storage controllers also support LUN Masking.

LUN (Logical Unit Number) Masking is an authorization process that makes a LUN available to some hosts and unavailable to other hosts.

LUN Masking is implemented primarily at the HBA (Host Bus Adapter) level. LUN Masking implemented at this level is vulnerable to any attack that compromises the HBA. Some storage controllers also support LUN Masking.