Decrease setup time using the ontape STDIO feature
You can dramatically improve the speed of setting up HDR
by using the ontape STDIO
feature.
Using this feature, ontape writes the data to the
shell's standard output during a backup, and then read it from standard
input during a restore. Combining a STDIO
backup
with a simultaneous STDIO
restore in a pipe using
a remote command interpreter (such as rsh or ssh), allows performing
the initial setup of an HDR (or RSS) secondary server using a single
command line. This saves storage space by not writing to or reading
from tape or disk, and does not require waiting for the backup to
finish before the restore can start.
See the IBM®
Informix Backup and Restore Guide for details
about using the STDIO
value.
This method for setting up HDR using ontape can be used regardless of which backup utility is used (ontape or ON-Bar).
-F
(fake) option on the source (backup) side
does not record the backup in the database server's reserved pages.
Also, any interactive dialog is suppressed and no prompts or questions
are displayed. You must also ensure that the remote part of the pipe
picks the appropriate environment for the remote Informix® instance.
The script must not produce any output other than the backup data
since this would be read by the restore process (for example, do not
enable tracing).The steps in the following table must be performed by user informix, the scripts must be executable, and, if called without a complete path, must be located in your home directory. You can use ssh instead of rsh if you require secure data transmission across the network.
- On the secondary server, install UDRs, UDTs, and DataBlade modules.
- On the primary server, install UDRs, UDTs, and DataBlade modules.
- On the primary server, register UDRs, UDTs, and modules.
- On the primary server, run the following command:
onmode -d primary secondary_server
- On the primary server, run the following command:
ontape -s -L 0 -t STDIO -F | rsh secondary_host ontape_HDR_restore.ksh
- On the secondary server, run the following command:
onmode -d secondary primary_server
#!/bin/ksh
# first get the proper Informix environment set
. hdr_sec.env
# redirecting stdout and stderr required since otherwise command might never return
ontape -p -t STDIO > /dev/null 2>&1
- On the secondary server, install UDRs, UDTs, and DataBlade modules.
- On the primary server, install UDRs, UDTs, and DataBlade modules.
- On the primary server, register UDRs, UDTs, and DataBlade modules.
- On the primary server, run the following command:
onmode -d primary secondary_server
- On the secondary server, run the following command:
rsh primary_host ontape_HDR_backup.ksh | ontape -p -t STDIO
- On the secondary server, run the following command:
onmode -d secondary primary_server
#!/bin/ksh
# first get the proper Informix environment set
. hdr_pri.env
ontape -s -L 0 -F -t STDIO