Using TCP/IP in Restricted State

Considerations for setting up and using BRMS in restricted state

When a backup is run on a system in a BRMS network that does not have any volumes available, BRMS will attempt to communicate with other systems in the network to take ownership of volumes to use during the backup.  Some backups are run with the operating system in restricted state.  If a backup is run in restricted state and there are not any volumes available, the backup will fail because the system will not be able to communicate with other systems in the BRMS network to take ownership of volumes.

BRMS can be set up to use an TCP/IP interface during backups that are done in restricted state so the system can take ownership of volumes from other systems in the BRMS network that are not in restricted state.  This will allow backups that are run in restricted state to continue even if no volumes are available on the system at the start of the backup.  

When a system is in restricted state, other systems in the BRMS network will not be able to send updates to it or request media from it.  If multiple systems in the BRMS network will be restricted state at the same time, it may be useful to run the Balancing Media in a BRMS Network (STRBALBRM) command before the systems are put into restricted state.  STRBALBRM will attempt to equally distribute scratch media between systems in the BRMS network, which may prevent backups from being run without available media on systems that are in restricted state.

In releases IBM i 6.1 and later, the BRMS GUI interface can be used to enable BRMS restricted state communication.

NOTES:

1. The restricted state interface must use a line type *ELAN, *TRLAN or *DDI, or a line description of *VIRTUALIP and line type *NONE.  To view the line type for your interface, at a command line interface enter CFGTCP and select option 1 - Work with TCP/IP interfaces.  The *VIRTUALIP interface, by itself, cannot communicate externally with other hosts. To communicate externally with other hosts. a *VIRTUALIP interface must be bound to a physical interface. Therefore, when using a *VIRTUALIP interface in BRMS, there must also be a corresponding physical interface defined.
2. The line description may not be attached to an NWID or NWSD.  To verify the interface is not attached to a NWID or NWSD, from a command line interface enter DSPLIND lindesc (where lindesc is the name of your line description) and verify that the Resource name is not *NWID or *NWSD.
3. BRMS can only start one interface per line description type.
4. Restricted state TCP will only be used to communicate out with other systems in the BRMS network that are not in restricted state. Other systems in the network will not be able to send updates to this system or request media from the system when in restricted state.
5. Systems that own media need to have TCP/IP up in order for other systems to take ownership of it's media. If a system is in a restricted state, or TCP/IP is ended, it's media cannot be shared with other systems in a BRMS network
6. The system has to be in restricted state for this to work.  If any subsystems are started after going into a restricted state, this will function will not work.
7. To verify the IP address entered you may use the BRMS GUI plugin, or from a command line interface run this command:

              QSYS/CALL QBRM/Q1AOLD PARM('TCPIPIFC' '*DISPLAY' '*ALL')

Additional information

In release IBM i V5R4M0, the following commands can be used to add, remove or display the TCP/IP or VIPA interfaces that BRMS will used during restricted state backups:

QSYS/CALL QBRM/Q1AOLD PARM('TCPIPIFC' '*ADD' 'interface')
QSYS/CALL QBRM/Q1AOLD PARM('TCPIPIFC' '*REMOVE' 'interface')
QSYS/CALL QBRM/Q1AOLD PARM('TCPIPIFC' '*REMOVE' '*ALL')
QSYS/CALL QBRM/Q1AOLD PARM('TCPIPIFC' '*DISPLAY' '*ALL')

Where 'interface' is the internet address of the system from which you issued this command and which you are using to communicate with the remote systems. Specify the interface in the form of nnn.nnn.nnn.nnn.
NOTE:

• This is not the IP address of other systems.
• When using Full System Flash Copy (FSFC), the IP address of the target backup system should be specified and not the IP address of the source system.

Example

QSYS/CALL QBRM/Q1AOLD PARM('TCPIPIFC' '*ADD' '19.71.1.28')

NOTES:

1. All parameters for this command must be entered in upper-case.
2. BRMS will not start any TCP/IP interfaces if the system is not completely in restricted state. Therefore any user-defined exit that is used to bring system to restricted state must make sure that system is completely in restricted state before starting the backup process.
3. Multiple interfaces can be specified by using the *ADD function for each interface. All interfaces that have been added will be started.
4. Once this command is run, it need not be run again unless you want to disable or re-enable restricted state TCP/IP.
5. BRMS cannot retrieve media from an owning system that is in restricted state, in FlashCopy mode, or not communicating.  In these cases, use the Balancing Media in a BRMS Network (STRBALBRM) command to assign media before systems go into a restricted state.
6. In releases IBM 6.1 and V5R4M0, to *REMOVE or *DISPLAY all interfaces by specifying *ALL for the interface parameter, the following PTFs or superseding PTFs are required:
        6.1 SI37276
        V5R4M0 SI37269