Hard Drive, Master Slave

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S1L1Y1

I would appreciate if somebody can explain to me what is the difference if a
drive is installed as a master or slave, also between primary and secondary?
Sol
 
Bob I said:
Only for IDE, not applicable to SATA. Master is the first drive connected
on an IDE cable, Slave is the second one. No Master, NO Slave, Primary is
the IDE channel 0, Secondary is IDE channel 1, .... so on up to channel 3

http://www.pcguide.com/ref/hdd/if/ide/confChannels-c.html
Click to expand...

Not entirely true, you can in fact have a slave drive without a master. And
the master slave designation has nothing to do with which drive is the first
drive connected to the ide cable, the system has no idea which drive you
connected first or second. In cable select mode the master is the drive
connected to the end of the cable, when using master/slave jumpering the
master is the drive jumpered as master no matter where on the cable it is.
But to answer the ops question, the master drive is designated as drive 0 as
is typically the boot drive.
 
Jerry said:
Not entirely true, you can in fact have a slave drive without a master. And
the master slave designation has nothing to do with which drive is the first
drive connected to the ide cable, the system has no idea which drive you
connected first or second. In cable select mode the master is the drive
connected to the end of the cable, when using master/slave jumpering the
master is the drive jumpered as master no matter where on the cable it is.
But to answer the ops question, the master drive is designated as drive 0 as
is typically the boot drive.
Click to expand...

It is completely true IF you follow the standards.
 
Bob I said:
It is completely true IF you follow the standards.
Click to expand...

According to your instructions, the Master/Slave resolution is decided by
time of installation on the cable and not position. How on earth does when
you plug a drive onto a cable more important then where. And again you are
wrong on your no master, no slave statement, when using master/slave
jumpering on disk drives, you don't need a master to have the slave drive
work.
 
S1L1Y1 said:
I would appreciate if somebody can explain to me what is the difference if
a drive is installed as a master or slave, also between primary and
secondary?
Sol
Click to expand...

In the days of parallel ATA (also incorrectly known as PATA) your PC would
have 2 IDE ports (or channels). These connect to PATA drives. One is
called the primary channel and will normally have the drive connected to it
from which the PC will boot. The other is the secondary port and only
connects to additional drives (but see below).

Each channel is capable of connecting to two disc drives known as the Master
and the Slave. Traditionally, the designation of master and slave was
achieved by the position of a jumper on the drive itself. However, these
days the drives are configured for a system called 'Cable Select' Basically
of the two drive connectors on the cable, one grounds pin 28 on the drive.
The drive interprests this that it is the master drive (this connector is
always at the end of the cable for technical reasons). The other connector
in the middle of the cable does not have pin 28 grounded. The drive
connected to this connector interprets that that it is the slave drive. At
system boot, the PC will always look for the Master Boot Record on the
master drive and attempt to boot an operating system from there.
Historically, the master drive had to be present but the slave was optional.
Motherboards are known that will work with a slave drive with no master
connected, but this is not to be recommended as the open circuit connector
at the end of the cable will reflect signals back down the cable.

More recent motherboards feature a BIOS that permits the boot drive being
located on the secondary IDE port, the change being made in a BIOS setting
(effectively interchanging the primary and secondary ports). This can
provide an easy method of dual booting.

In more recent times with the switch to SATA disc drives, each SATA port
only supports one disc drive, so the designation master and slave is
redundant. Most motherboards have more than 2 SATA ports to facilitate the
connection of SATA DVD drives. Generally most BIOSes for these motherboards
permit the user to decide from which port the system will boot (or more
usually designate the order of priority, such that if a bootable disc isn't
found on the first priority port, it goes to look at the next one and so
on).

HTH
 
Bob I said:
Only for IDE, not applicable to SATA. Master is the first drive connected
on an IDE cable, Slave is the second one. No Master, NO Slave, Primary is
the IDE channel 0, Secondary is IDE channel 1, .... so on up to channel 3
Click to expand...

If only one drive is connected, it should always be connected to the end of
the cable not the nmiddle. It follows that the master drive should be at
the end of the cable and this is, in fact, how cable select is configured.
 
M.I.5¾ said:
If only one drive is connected, it should always be connected to the end of
the cable not the nmiddle. It follows that the master drive should be at
the end of the cable and this is, in fact, how cable select is configured.
Click to expand...
Correct.
 
Jerry said:
According to your instructions, the Master/Slave resolution is decided by
time of installation on the cable and not position. How on earth does when
you plug a drive onto a cable more important then where. And again you are
wrong on your no master, no slave statement, when using master/slave
jumpering on disk drives, you don't need a master to have the slave drive
work.
Click to expand...

Maybe and certainly not if you adhere to the standards, also "First and
Second" has nothing to do with WHEN you put a drive in the case. You're
just being silly now.

http://www.pcguide.com/ref/hdd/if/ide/conf_Jumpering.htm

The only practical difference between master and slave is that the PC
considers the master "first" and the slave "second" in general terms.
 
M.I.5¾ said:
If only one drive is connected, it should always be connected to the end
of the cable not the nmiddle. It follows that the master drive should be
at the end of the cable and this is, in fact, how cable select is
configured.
Click to expand...
Correct.
 
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