The Software RAID Inflection Point
-
@FATeknollogee said in The Software RAID Inflection Point:
@dafyre said in The Software RAID Inflection Point:
Blind swap isn't an issue with hardware raid, and in general, I think, for SMBs, at least, HW raid win's because of that.
Agreed, but if MD is "better", why recommend a solution that is not as good!
Because you have to say "better", not just better. It's different. Software RAID is cheaper, faster and more flexible. But hardware RAID is simpler and better understood and when it comes to storage in the SMB, that's what matters most. Faster is of basically no importance in the SMB space; everyone thinks that it is, but it just isn't.
-
@Dashrender said in The Software RAID Inflection Point:
@travisdh1 said in The Software RAID Inflection Point:
@FATeknollogee said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
Because the software RAID would rarely, if ever, be aware of the type of hardware it's it, i.e. a HP server, a Dell server, etc - it probably has no way of mapping a drive to a specific port on the chassis and lighting the lights, etc - the things needed to make Blind Swap work.
In today's world with all the smart people we have, no one can write software that can map drives to a chassis?
If a hardware vendor wanted to, they easily could, but it would mean seriously hampering the number of options available on a general purpose server platform. NAS vendors do this all the time.
NAS vendors do it because they control all the hardware. Sure, Dell could do it for their system, and HP for theirs, etc - but why? They'd rather sell you a RAID card.
Actually they can't, because they don't know the use case. It's not about controlling all the hardware, it's about controlling everything from the disk to the application. Hardware RAID does it by pre-determining how it will be used.
-
@travisdh1 said in The Software RAID Inflection Point:
@FATeknollogee said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
Because the software RAID would rarely, if ever, be aware of the type of hardware it's it, i.e. a HP server, a Dell server, etc - it probably has no way of mapping a drive to a specific port on the chassis and lighting the lights, etc - the things needed to make Blind Swap work.
In today's world with all the smart people we have, no one can write software that can map drives to a chassis?
If a hardware vendor wanted to, they easily could, but it would mean seriously hampering the number of options available on a general purpose server platform. NAS vendors do this all the time.
Exactly. It's that one is general purpose that makes it complicated.
-
@scottalanmiller said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
@travisdh1 said in The Software RAID Inflection Point:
@FATeknollogee said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
Because the software RAID would rarely, if ever, be aware of the type of hardware it's it, i.e. a HP server, a Dell server, etc - it probably has no way of mapping a drive to a specific port on the chassis and lighting the lights, etc - the things needed to make Blind Swap work.
In today's world with all the smart people we have, no one can write software that can map drives to a chassis?
If a hardware vendor wanted to, they easily could, but it would mean seriously hampering the number of options available on a general purpose server platform. NAS vendors do this all the time.
NAS vendors do it because they control all the hardware. Sure, Dell could do it for their system, and HP for theirs, etc - but why? They'd rather sell you a RAID card.
Actually they can't, because they don't know the use case. It's not about controlling all the hardware, it's about controlling everything from the disk to the application.
What do you mean that they don't know the use case...?
Does it matter? We just want a way to flash the "help me" light on a dying/dead disk, lol.
Would that not be something controllable by the firmware of the HD?
-
@dafyre said in The Software RAID Inflection Point:
@scottalanmiller said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
@travisdh1 said in The Software RAID Inflection Point:
@FATeknollogee said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
Because the software RAID would rarely, if ever, be aware of the type of hardware it's it, i.e. a HP server, a Dell server, etc - it probably has no way of mapping a drive to a specific port on the chassis and lighting the lights, etc - the things needed to make Blind Swap work.
In today's world with all the smart people we have, no one can write software that can map drives to a chassis?
If a hardware vendor wanted to, they easily could, but it would mean seriously hampering the number of options available on a general purpose server platform. NAS vendors do this all the time.
NAS vendors do it because they control all the hardware. Sure, Dell could do it for their system, and HP for theirs, etc - but why? They'd rather sell you a RAID card.
Actually they can't, because they don't know the use case. It's not about controlling all the hardware, it's about controlling everything from the disk to the application.
What do you mean that they don't know the use case...?
Does it matter? We just want a way to flash the "help me" light on a dying/dead disk, lol.
Would that not be something controllable by the firmware of the HD?
What if the problem is the cable, motherboard, or somewhere else. That's why the hdd lights are normally controlled at the BIOS level.
-
@travisdh1 said in The Software RAID Inflection Point:
@dafyre said in The Software RAID Inflection Point:
@scottalanmiller said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
@travisdh1 said in The Software RAID Inflection Point:
@FATeknollogee said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
Because the software RAID would rarely, if ever, be aware of the type of hardware it's it, i.e. a HP server, a Dell server, etc - it probably has no way of mapping a drive to a specific port on the chassis and lighting the lights, etc - the things needed to make Blind Swap work.
In today's world with all the smart people we have, no one can write software that can map drives to a chassis?
If a hardware vendor wanted to, they easily could, but it would mean seriously hampering the number of options available on a general purpose server platform. NAS vendors do this all the time.
NAS vendors do it because they control all the hardware. Sure, Dell could do it for their system, and HP for theirs, etc - but why? They'd rather sell you a RAID card.
Actually they can't, because they don't know the use case. It's not about controlling all the hardware, it's about controlling everything from the disk to the application.
What do you mean that they don't know the use case...?
Does it matter? We just want a way to flash the "help me" light on a dying/dead disk, lol.
Would that not be something controllable by the firmware of the HD?
What if the problem is the cable, motherboard, or somewhere else. That's why the hdd lights are normally controlled at the BIOS level.
If that's the case, then why does the bios itself not flash the dead drive lights when using mdraid?
-
@travisdh1 said in The Software RAID Inflection Point:
@dafyre said in The Software RAID Inflection Point:
@scottalanmiller said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
@travisdh1 said in The Software RAID Inflection Point:
@FATeknollogee said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
Because the software RAID would rarely, if ever, be aware of the type of hardware it's it, i.e. a HP server, a Dell server, etc - it probably has no way of mapping a drive to a specific port on the chassis and lighting the lights, etc - the things needed to make Blind Swap work.
In today's world with all the smart people we have, no one can write software that can map drives to a chassis?
If a hardware vendor wanted to, they easily could, but it would mean seriously hampering the number of options available on a general purpose server platform. NAS vendors do this all the time.
NAS vendors do it because they control all the hardware. Sure, Dell could do it for their system, and HP for theirs, etc - but why? They'd rather sell you a RAID card.
Actually they can't, because they don't know the use case. It's not about controlling all the hardware, it's about controlling everything from the disk to the application.
What do you mean that they don't know the use case...?
Does it matter? We just want a way to flash the "help me" light on a dying/dead disk, lol.
Would that not be something controllable by the firmware of the HD?
What if the problem is the cable, motherboard, or somewhere else. That's why the hdd lights are normally controlled at the BIOS level.
What? How would a RAID card know if it's a cable or the backplane causing the issue?
-
@Dashrender said in The Software RAID Inflection Point:
@travisdh1 said in The Software RAID Inflection Point:
@dafyre said in The Software RAID Inflection Point:
@scottalanmiller said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
@travisdh1 said in The Software RAID Inflection Point:
@FATeknollogee said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
Because the software RAID would rarely, if ever, be aware of the type of hardware it's it, i.e. a HP server, a Dell server, etc - it probably has no way of mapping a drive to a specific port on the chassis and lighting the lights, etc - the things needed to make Blind Swap work.
In today's world with all the smart people we have, no one can write software that can map drives to a chassis?
If a hardware vendor wanted to, they easily could, but it would mean seriously hampering the number of options available on a general purpose server platform. NAS vendors do this all the time.
NAS vendors do it because they control all the hardware. Sure, Dell could do it for their system, and HP for theirs, etc - but why? They'd rather sell you a RAID card.
Actually they can't, because they don't know the use case. It's not about controlling all the hardware, it's about controlling everything from the disk to the application.
What do you mean that they don't know the use case...?
Does it matter? We just want a way to flash the "help me" light on a dying/dead disk, lol.
Would that not be something controllable by the firmware of the HD?
What if the problem is the cable, motherboard, or somewhere else. That's why the hdd lights are normally controlled at the BIOS level.
What? How would a RAID card know if it's a cable or the backplane causing the issue?
With a RAID card, it flashes the light, because it knows where the problem lies. It's when you don't have hardware RAID that you have the problem.
-
@dafyre said in The Software RAID Inflection Point:
@scottalanmiller said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
@travisdh1 said in The Software RAID Inflection Point:
@FATeknollogee said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
Because the software RAID would rarely, if ever, be aware of the type of hardware it's it, i.e. a HP server, a Dell server, etc - it probably has no way of mapping a drive to a specific port on the chassis and lighting the lights, etc - the things needed to make Blind Swap work.
In today's world with all the smart people we have, no one can write software that can map drives to a chassis?
If a hardware vendor wanted to, they easily could, but it would mean seriously hampering the number of options available on a general purpose server platform. NAS vendors do this all the time.
NAS vendors do it because they control all the hardware. Sure, Dell could do it for their system, and HP for theirs, etc - but why? They'd rather sell you a RAID card.
Actually they can't, because they don't know the use case. It's not about controlling all the hardware, it's about controlling everything from the disk to the application.
What do you mean that they don't know the use case...?
Does it matter? We just want a way to flash the "help me" light on a dying/dead disk, lol.
Would that not be something controllable by the firmware of the HD?
That's not what blind swap does.
-
@scottalanmiller said in The Software RAID Inflection Point:
@dafyre said in The Software RAID Inflection Point:
@scottalanmiller said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
@travisdh1 said in The Software RAID Inflection Point:
@FATeknollogee said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
Because the software RAID would rarely, if ever, be aware of the type of hardware it's it, i.e. a HP server, a Dell server, etc - it probably has no way of mapping a drive to a specific port on the chassis and lighting the lights, etc - the things needed to make Blind Swap work.
In today's world with all the smart people we have, no one can write software that can map drives to a chassis?
If a hardware vendor wanted to, they easily could, but it would mean seriously hampering the number of options available on a general purpose server platform. NAS vendors do this all the time.
NAS vendors do it because they control all the hardware. Sure, Dell could do it for their system, and HP for theirs, etc - but why? They'd rather sell you a RAID card.
Actually they can't, because they don't know the use case. It's not about controlling all the hardware, it's about controlling everything from the disk to the application.
What do you mean that they don't know the use case...?
Does it matter? We just want a way to flash the "help me" light on a dying/dead disk, lol.
Would that not be something controllable by the firmware of the HD?
That's not what blind swap does.
No, it doesn't. But if you know which drive is failing, that makes it easier to swap the correct drive.
-
@travisdh1 said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
@travisdh1 said in The Software RAID Inflection Point:
@dafyre said in The Software RAID Inflection Point:
@scottalanmiller said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
@travisdh1 said in The Software RAID Inflection Point:
@FATeknollogee said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
Because the software RAID would rarely, if ever, be aware of the type of hardware it's it, i.e. a HP server, a Dell server, etc - it probably has no way of mapping a drive to a specific port on the chassis and lighting the lights, etc - the things needed to make Blind Swap work.
In today's world with all the smart people we have, no one can write software that can map drives to a chassis?
If a hardware vendor wanted to, they easily could, but it would mean seriously hampering the number of options available on a general purpose server platform. NAS vendors do this all the time.
NAS vendors do it because they control all the hardware. Sure, Dell could do it for their system, and HP for theirs, etc - but why? They'd rather sell you a RAID card.
Actually they can't, because they don't know the use case. It's not about controlling all the hardware, it's about controlling everything from the disk to the application.
What do you mean that they don't know the use case...?
Does it matter? We just want a way to flash the "help me" light on a dying/dead disk, lol.
Would that not be something controllable by the firmware of the HD?
What if the problem is the cable, motherboard, or somewhere else. That's why the hdd lights are normally controlled at the BIOS level.
What? How would a RAID card know if it's a cable or the backplane causing the issue?
With a RAID card, it flashes the light, because it knows where the problem lies. It's when you don't have hardware RAID that you have the problem.
There again, if the lights are controlled at the BIOS level, why does having a hardware raid card matter?
-
If the md authors would make some sort of blinky light function that would be sweet and solve this issue. mdadm -blink /dev/sde
-
@momurda said in The Software RAID Inflection Point:
If the md authors would make some sort of blinky light function that would be sweet and solve this issue. mdadm -blink /dev/sde
How do you do that for cases that only have a single HDD light?
-
@dafyre said in The Software RAID Inflection Point:
@travisdh1 said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
@travisdh1 said in The Software RAID Inflection Point:
@dafyre said in The Software RAID Inflection Point:
@scottalanmiller said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
@travisdh1 said in The Software RAID Inflection Point:
@FATeknollogee said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
Because the software RAID would rarely, if ever, be aware of the type of hardware it's it, i.e. a HP server, a Dell server, etc - it probably has no way of mapping a drive to a specific port on the chassis and lighting the lights, etc - the things needed to make Blind Swap work.
In today's world with all the smart people we have, no one can write software that can map drives to a chassis?
If a hardware vendor wanted to, they easily could, but it would mean seriously hampering the number of options available on a general purpose server platform. NAS vendors do this all the time.
NAS vendors do it because they control all the hardware. Sure, Dell could do it for their system, and HP for theirs, etc - but why? They'd rather sell you a RAID card.
Actually they can't, because they don't know the use case. It's not about controlling all the hardware, it's about controlling everything from the disk to the application.
What do you mean that they don't know the use case...?
Does it matter? We just want a way to flash the "help me" light on a dying/dead disk, lol.
Would that not be something controllable by the firmware of the HD?
What if the problem is the cable, motherboard, or somewhere else. That's why the hdd lights are normally controlled at the BIOS level.
What? How would a RAID card know if it's a cable or the backplane causing the issue?
With a RAID card, it flashes the light, because it knows where the problem lies. It's when you don't have hardware RAID that you have the problem.
There again, if the lights are controlled at the BIOS level, why does having a hardware raid card matter?
Because you still want blind swap.
-
@momurda said in The Software RAID Inflection Point:
If the md authors would make some sort of blinky light function that would be sweet and solve this issue. mdadm -blink /dev/sde
That requires special hardware, though. So could be an option sometimes, but not others.
-
@travisdh1 said in The Software RAID Inflection Point:
@momurda said in The Software RAID Inflection Point:
If the md authors would make some sort of blinky light function that would be sweet and solve this issue. mdadm -blink /dev/sde
How do you do that for cases that only have a single HDD light?
Or none.
-
@dafyre said in The Software RAID Inflection Point:
@scottalanmiller said in The Software RAID Inflection Point:
@dafyre said in The Software RAID Inflection Point:
@scottalanmiller said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
@travisdh1 said in The Software RAID Inflection Point:
@FATeknollogee said in The Software RAID Inflection Point:
@Dashrender said in The Software RAID Inflection Point:
Because the software RAID would rarely, if ever, be aware of the type of hardware it's it, i.e. a HP server, a Dell server, etc - it probably has no way of mapping a drive to a specific port on the chassis and lighting the lights, etc - the things needed to make Blind Swap work.
In today's world with all the smart people we have, no one can write software that can map drives to a chassis?
If a hardware vendor wanted to, they easily could, but it would mean seriously hampering the number of options available on a general purpose server platform. NAS vendors do this all the time.
NAS vendors do it because they control all the hardware. Sure, Dell could do it for their system, and HP for theirs, etc - but why? They'd rather sell you a RAID card.
Actually they can't, because they don't know the use case. It's not about controlling all the hardware, it's about controlling everything from the disk to the application.
What do you mean that they don't know the use case...?
Does it matter? We just want a way to flash the "help me" light on a dying/dead disk, lol.
Would that not be something controllable by the firmware of the HD?
That's not what blind swap does.
No, it doesn't. But if you know which drive is failing, that makes it easier to swap the correct drive.
True, but we already have that feature.
-
Here is the software RAID blink command for Solaris:
http://prefetch.net/blog/index.php/2007/03/13/locating-disk-drives-in-a-sea-of-a5200s/
-
And the third entry here shows how to do this with Linux, with or without MD RAID.
http://serverfault.com/questions/64239/physically-identify-the-failed-hard-drive
-
@scottalanmiller said in The Software RAID Inflection Point:
And the third entry here shows how to do this with Linux, with or without MD RAID.
http://serverfault.com/questions/64239/physically-identify-the-failed-hard-drive
That's what we were looking for. Why couldn't something like that be integrated with mdraid, much as momurda suggested?
When mdraid detects a failed drive, kick off a script that fires off smartctl or ledctl or something?
