Requires Optional SwitchOver/UX Software

NAME

switchreadp − monitor health of primary host(s)

SYNOPSIS

switchreadp [-f infofile]

Remarks

This command requires installation of optional SwitchOver/UX software (not included in the standard HP-UX operating system) before it can be used. 

DESCRIPTION

switchreadp runs the readpulse daemon, which monitors state-of-health messages from the primary hosts of the SwitchOver/UX group.  When the daemon detects that one of the primaries has failed, it begins a takeover procedure, eventually causing the standby system processor to reboot from the failed primary’s disks. 

Options

-f infofile Names the information file.  Default is /etc/switch/Switchinfo. 

The command is run at bootup by the standby host only, usually from /etc/inittab. 

switchreadp monitors each primary host having a prihost# entry in the standby’s section of the information file.  The # is a single character from 0-9.  The daemon listens on each lan with a lan# entry in this section.  The numbers for these two types of entries are unrelated. 

When the daemon determines that a primary has failed, it executes /etc/switch/become, a shell script that performs the takeover. 

switchreadp examines several entries in the information file.  The following entries appear in the section describing each primary:

timeout Time (in seconds) after which readpulse should assume that this primary has failed. 

bootpath Primary boot path used when rebooting the primary host.  Passed to become. 

bootmir Boot path of the alternate boot device used for rebooting the primary host.  For mirroring with DataPair, the alternate device is the secondary half of the mirrored boot device.  For mirroring with Logical Volume Manager, the alternate device is a second physical volume configured as a boot device.  If the root is not mirrored, this entry is omitted.  Passed to become. 

bootthird Boot path of a third boot device used for rebooting the primary host.  The third boot device is a third physical volume configured as a boot device.  If the root is not mirrored using Logical Volume Manager, this entry is omitted. 

The following entries appear in the section describing the standby:

rtprio Gives the real-time priority for the process (see rtprio(2)), or no if no real-time priority is desired.  The default is 0. 

lockmem Tells whether the daemon should be locked into main memory (yes) or not (no).  The default is yes. 

logfile Names the file to which readpulse writes error messages.  Messages describing the takeover also appear. 

prihost# Names the primary host to monitor.  # is a single character from 0-9. 

rootdisk# Names the (raw) root disk.  # is a single character from 0-9.  The root named belongs to the host named in the corresponding prihost# entry.  The name is the one used by the standby.  Passed to become. 

rootmir# Similar to rootdisk#, but names the second root device.  If the root is not mirrored, this entry is omitted.  Passed to become. 

rootthird# Similar to rootdisk#, but names the third root device.  If the root is not mirrored, this entry is omitted.  Passed to become. 

Only users with appropriate privileges can run switchreadp. 

AUTHOR

switchreadp was developed by HP. 

FILES

/dev/lan* interface to LAN cards

/etc/switch/Switchinfo default SwitchOver/UX information file

/etc/switch/readpulse readpulse daemon

/etc/switch/become performs takeover

/etc/switch/incdate adjusts clock on takeover

/etc/switch/switchdiskl locks disks on takeover

/etc/switch/checkroot checks disks on takeover

/etc/switch/setboot sets boot paths on takeover

SEE ALSO

switchsetlan(1m), switchheartb(1m), switchdiskl(1m), switchsetflg(1m), switchinfo(4). 

Hewlett-Packard Company  —  HP-UX Release 9.03: April 1994