Chapter 4. Switch Configuration

This chapter discusses the following:


Note: No configuration specific to CXFS is required for InfiniBand and serial-attached storage (SAS) switches.


Brocade Switch

This section discusses the following:

See also “Change the Brocade™ Password when Prompted” in Chapter 2.

Brocade Firmware

All Brocade switches contained within the SAN fabric must have the appropriate Brocade firmware. For the currently supported firmware, see the CXFS general release notes.

If the current firmware level of the switches must be upgraded, please contact your local SGI service representative or customer support center.

The Brocade switch must be configured so that its Ethernet interface is accessible via the telnet (default) or ssh from all CXFS administration nodes. The fencing network connected to the Brocade switch must be physically separate from the private heartbeat network.


Caution: In order for I/O fencing to succeed, the admin user must not be logged in.

Switches using 4.x.x.x or later firmware permit multiple login sessions. However, CXFS I/O fencing requires a login lockout for global mutual exclusion when a fencing race occurs. Therefore, you must configure these switches to set the maximum allowed simultaneous login sessions for the admin user to 1. (Brocade switches running 3.x.x.x firmware are shipped with the required restrictions configured by default).

For more information, see “Using SGI Knowledgebase” in Chapter 15.

Verifying the Brocade Switch Firmware Version

To verify the firmware version, log into the switch as user admin and use the version command, as shown in the following examples:

workstation% telnet brocade1
Trying 169.238.221.224...
Connected to brocade1.example.com
Escape character is '^]'.

Fabric OS (tm)  Release v2.6.0d

login: admin
Password:
brocade1:admin> version
Kernel:     5.4
Fabric OS:  v2.6.0d            <== Firmware Revision
Made on:    Fri May 17 16:33:09 PDT 2002
Flash:      Fri May 17 16:34:55 PDT 2002
BootProm:   Thu Jun 17 15:20:39 PDT 1999
brocade1:admin>

Verifying the Brocade License

To verify the Brocade license, log into the switch as user admin and use the licenseshow command, as shown in the following example:

brocade:admin> licenseshow
dcRyzyScSedSz0p:
    Web license
    Zoning license
    SES license
    Fabric license
SQQQSyddQ9TRRdUP:
    Release v2.2 license

Limiting Login Sessions

You must limit the maximum allowed simultaneous telnet or ssh login sessions:

Brocade 12000/24000/48000 Models

To limit the maximum allowed simultaneous telnet or ssh login sessions for the admin user to 1 on the Brocade 12000/24000/48000 models, do the following:

  1. Connect to the switch as root.

  2. Use the haShow command to make sure that both central processors are up. This is indicated by the message Heartbeat Up within the output of the haShow command. If it is not up, wait a few minutes and run haShow again to check for the status.

  3. Issue the sync command on the filesystems to avoid filesystem corruption:

    # rsh 10.0.0.5 sync
    # rsh 10.0.0.6 sync

  4. Edit the /etc/profile file to change the max_telnet_sessions (for either telnet or ssh) from 2 to 1 and place the information in a new file. For example:

    # cd /etc
    # sed -e 's/max_telnet_sessions=2/max_telnet_sessions=1/' profile >profile.new

  5. Distribute the new profile to both partitions and central processors. For example:

    # rcp /etc/profile.new 10.0.0.5:/etc/profile
    # rcp /etc/profile.new 10.0.0.5:/mnt/etc/profile
    # rcp /etc/profile.new 10.0.0.6:/etc/profile
    # rcp /etc/profile.new 10.0.0.6:/mnt/etc/profile

  6. Issue the sync command again to avoid filesystem corruption:

    # rsh 10.0.0.5 sync
    # rsh 10.0.0.6 sync

Other Brocade Models

To limit the maximum allowed simultaneous telnet or ssh login sessions for the admin user to 1 on the Brocade 200E/300/3250/3252/3850/3852/3900/4100/4900/5000/5100/5300 models, do the following:

  1. Connect to the switch as root.

  2. Issue the sync command to avoid filesystem corruption:

    # sync

  3. Edit the /etc/profile file to change the max_telnet_sessions (for either telnet or ssh) from 2 to 1 and place the information in a new file. For example:

    # cd /etc
    # sed -e 's/max_telnet_sessions=2/max_telnet_sessions=1/' profile >profile.new
    

  4. Distribute the edited profile file to both partitions on both central processors. For example:

    # cp profile.new profile
    # cp profile.new /mnt/etc/profile

  5. Issue the sync command again to avoid filesystem corruption:

    # sync

Changing the Brocade FC Cable Connections

To change Brocade Fibre Channel cable connections used by nodes in the CXFS cluster, do the following:

  1. Cleanly shut down CXFS services on the nodes affected by the cable change. Use the CXFS GUI or cxfs_admin.

  2. Rearrange the cables as required.

  3. Restart CXFS services.

  4. Reconfigure I/O fencing if required. You must perform this step if I/O fencing is enabled on the cluster and if you added/removed any Brocade switches. You must use the CXFS GUI or cxfs_admin to add or remove switches from the CXFS configuration as required.

  5. If any CXFS client nodes are connected to a new (or different) Brocade switch, restart CXFS services on those nodes. This will ensure that the CXFS administration servers can correctly identify the Brocade ports used by all clients.

Enabling In-Order-Delivery of Packets

To avoid dropping frames, ensure that the in-order-delivery (IOD) feature route.delayReroute is enabled (set to 1) as displayed by the Brocade configShow output.

For example, the following output shows that the feature is disabled (set to 0):

brocade:admin> configshow
date = Mon Mar 11 08:30:26 2013
[Switch Configuration Begin : 0]
...
route.delayReroute:0
...

To change the setting to 1, enter the iodSet command:

brocade:admin> iodSet


Note: You can change this setting without rebooting the switch.

The output would then show the feature is enabled (set to 1):

brocade:admin> configshow
date = Mon Mar 11 08:30:26 2013
[Switch Configuration Begin : 0]
...
route.delayReroute:1
...

Suppressing RSCN

Enable (turn ON) registered state change notification (RSCN) suppression if the port is connected to a host HBA or disable (turn OFF) suppression for all other ports. Use the portcfgshow command to display the current settings.

Use the following command on the switch:

switch> portcfg rscnsupr [Slot/]Port[-Range] --enable|--disable

For example, suppose that ports 4 through 7 go from the switch to nodes in the cluster. You would enter the following to enable RSCN suppression for ports 4 through 7:

switch> portcfg rscnsupr 4-7 --enable

switch> portcfgshow

Locked L_Port     .. .. .. ..   .. .. .. ..   .. .. .. ..   .. .. .. .. 
Locked G_Port     .. .. .. ..   .. .. .. ..   .. .. .. ..   .. .. .. .. 
Disabled E_Port   .. .. .. ..   .. .. .. ..   .. .. .. ..   .. .. .. .. 
ISL R_RDY Mode    .. .. .. ..   .. .. .. ..   .. .. .. ..   .. .. .. .. 
RSCN Suppressed   .. .. .. ..   ON ON ON ON   .. .. .. ..   .. .. .. .. 
Persistent Disable.. ON ON ON   .. ON ON ON   ON ON ON ON   ON .. .. .. 
NPIV capability   ON ON ON ON   ON ON ON ON   ON ON ON ON   ON ON ON ON

QLogic® Fibre Channel Switch

All QLogic Fibre Channel (FC) switches contained within the SAN fabric must have the appropriate QLogic firmware installed, as shown in the CXFS general release notes.

For more information, see the QLogic SANbox2-64 Switch Management User's Guide.


Caution: The admin state is required for I/O fencing. To avoid interference with fencing, release admin mode as soon as possible. Do not leave admin mode sessions open.

The default port configuration on a QLogic 9200 FC switch is not compatible with the CXFS environment. To use the appropriate port configuration, change the following parameters:

LinkSpeed  

Set to the appropriate value, such as 2 for 2 GB/s. (In some cases, Auto does not function properly.)

PortType 

Enter the appropriate type, usually F. (You cannot use the GL autonegotiated mode.)

NoClose 

Set to True to prevent the Fibre Channel circuit from shutting down during a host reboot.

IOStreamGuard 

Set to Enable if the port is connected to a host HBA or to Disable if for all other ports. (You cannot use Auto mode because most HBAs cannot negotiate this.)

To modify these parameters, use the admin command. For example, for a port connected to an SGI UV® 100 system:

SANbox #> admin start

SANbox (admin) #> config edit
  The config named default is being edited.

SANbox (admin-config) #> set config port 31


  A list of attributes with formatting and current values will follow.
  Enter a new value or simply press the ENTER key to accept the current value.
  If you wish to terminate this process before reaching the end of the list
  press 'q' or 'Q' and the ENTER key to do so.

  Configuring Port Number: 31
  ------------------------

  AdminState       (1=Online, 2=Offline, 3=Diagnostics, 4=Down) [Online]  
  LinkSpeed        (1=1Gb/s, 2=2Gb/s, 4=4Gb/s, A=Auto)          [Auto  ]  2
  PortType         (GL / G / F / FL / Donor)                    [GL    ]  F
  SymPortName      (string, max=32 chars)                       [Port31]  UV100
  ALFairness       (True / False)                               [False ]  
  DeviceScanEnable (True / False)                               [True  ]  
  ForceOfflineRSCN (True / False)                               [False ]  
  ARB_FF           (True / False)                               [False ] 
  InteropCredit    (decimal value, 0-255)                       [0     ]  
  ExtCredit        (dec value, increments of 15, non-loop only) [0     ]  
  FANEnable        (True / False)                               [True  ]  
  AutoPerfTuning   (True / False)                               [True  ]  
  MSEnable         (True / False)                               [True  ]  
  NoClose          (True / False)                               [False ]  True
  IOStreamGuard    (Enable / Disable / Auto)                    [Auto  ]  Enable  
  PDISCPingEnable  (True / False)                               [True  ]  

  Finished configuring attributes.
  This configuration must be saved (see config save command) and 
  activated (see config activate command) before it can take effect.
  To discard this configuration use the config cancel command.
  ....

SANbox (admin-config) #> config save
  The config named default has been saved.

SANbox (admin) #> config activate

  The currently active configuration will be activated.
  Please confirm (y/n): [n] y

SANbox (admin) #> admin end

SANbox #> show config port 31

  Configuration Name: default
  -------------------

  Port Number: 31
  ------------
  AdminState         Online
  LinkSpeed          2Gb/s
  PortType           F
  SymbolicName       UV100
  ALFairness         False
  DeviceScanEnabled  True
  ForceOfflineRSCN   False
  ARB_FF             False
  InteropCredit      0
  ExtCredit          0
  FANEnabled         True
  AutoPerfTuning     True
  MSEnabled          True
  NoClose            True
  IOStreamGuard      Enabled
  PDISCPingEnabled   True