Special considerations for iSCSI attached systems
For iSCSI attached servers, the server hardware state is used to control
access to the hardware and ensure that only one NWSD is using the hardware
at any point in time. When starting (varying on) the NWSD, the specific behavior
for an iSCSI attached server depends on the type of service processor that
the server has:
- For xSeries® servers with a BMC service processor, the hardware must initially
be in a powered off state.
- For xSeries server with an RSA II or an IBM® BladeCenter™ with a Management Module, the hardware
must not be booted to an operating system (for example DOS or Windows). An xSeries system that is sitting at the insert diskette prompt is allowed,
but the system will wait for a period of time to ensure that no other system
is attempting to use the system.
Otherwise, the start operation will fail. When shutting down (varying
off) the NWSD, the NWSD's xSeries or BladeCenter blade hardware will be left in
a powered off state.
In addition to the case when an NWSD is currently using the server hardware,
there are other possible reasons that the server hardware is in a powered
on state. For example, the server hardware may have been powered on to perform
hardware setup, such as loading firmware or changing BIOS settings. Another
example is when the server operating system has encountered an unrecoverable
error, resulting in a failed server, but leaving the hardware in a powered
on state. For these cases, starting an NWSD in the normal way may fail because
the server hardware is not in a powered off state or the service processor
indicates that an operating system is still running.
There are a couple of ways to recover from this:
- If an NWSD is currently using the hardware, but the server operating system
failed, then try shutting down the server. In most cases, this will power
off the server hardware and make it available to the same or another NWSD.
If shutting down the NWSD does not resolve the problem try the method described
below.
- When starting an NWSD, there is a reset system option to force the server
hardware to be reset during the start of the NWSD. You can use this option
to start an NWSD that uses server hardware that is in a state that would normally
cause the start (vary on) of the server to fail.
Attention: Use the reset system option only when you are sure that the server
hardware is not currently being used by another NWSD. If you use the reset
system option to start an NWSD when there is another NWSD that is running
on the hardware, the other NWSD will fail and can incur data loss or corruption.
To reset a remote system using iSeries™ Navigator, follow these steps:
- Expand Integrated Server Administration.
- Expand Servers.
- Right-click a server from the list available.
- Select Start with options...
- Check the Reset remote system option.
- Click Start. A confirmation panel is shown.
- Click Start on the confirmation panel to start and
reset the remote system.
If you want to use a CL command, see the Reset system (RESETSYS) keyword
on the Vary Configuration (VRYCFG) command.
