Good hardware for mdadm
Hello,
I like mdadm and I am using it many years. But in my opinion it has one
disadvantage: when the MBR of the boot-disk is corrupt, the machine will not boot.
A bios could check this. Wait for some kind of signal from Grub or Linux, and after a timeout boot from another disk. But I don't know about a bios with that feature.
A PCIe card could do something like that, but I don't know about such a PCIe card.
Is there such hardware?
What do you do to avoid this problem?
With regards,
Paul van der Vlis.
Signature · 2 lines
Paul van der Vlis Linux systeembeheer, Groningen http://www.vandervlis.nl/
i use two or more boot disks, if the first raid1 disk don't boot bios go to second boot disk, third, etc etc, you must write grub to mbr of each disk
i'm using dell server r410 if i'm not wrong
2014-08-29 17:31 GMT-03:00 Paul van der Vlis <[email protected]>:
Quoted 30 lines
Hello,
I like mdadm and I am using it many years. But in my opinion it has one
disadvantage: when the MBR of the boot-disk is corrupt, the machine will not boot.A bios could check this. Wait for some kind of signal from Grub or Linux, and after a timeout boot from another disk. But I don't know about a bios with that feature.
A PCIe card could do something like that, but I don't know about such a PCIe card.
Is there such hardware?
What do you do to avoid this problem?With regards,
Paul van der Vlis.--
Paul van der Vlis Linux systeembeheer, Groningen
http://www.vandervlis.nl/--
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Signature · 1 line
Roberto Spadim
Hi Roberto,
op 29-08-14 22:44, Roberto Spadim schreef:
Quoted 2 lines
i use two or more boot disks, if the first raid1 disk don't boot bios go to second boot disk, third, etc etc,
In my opinion this only works when the boot-disk is completely defect or removed. Not when the data in the MBR on that boot-disk is corrupt.
Or did you test this, or do you have other reasons to believe that your bios will handle this correct?
With the boot-disk I mean the disk what's in the bios the first disk. So this could also be the second raid1 disk. Or an USB stick.
Quoted 1 line
you must write grub to mbr of each disk
Of course.
With regards,
Paul van der Vlis.
Quoted 36 lines
i'm using dell server r410 if i'm not wrong
2014-08-29 17:31 GMT-03:00 Paul van der Vlis <[email protected]>:
Quoted 30 lines
Hello,
I like mdadm and I am using it many years. But in my opinion it has one
disadvantage: when the MBR of the boot-disk is corrupt, the machine will not boot.A bios could check this. Wait for some kind of signal from Grub or Linux, and after a timeout boot from another disk. But I don't know about a bios with that feature.
A PCIe card could do something like that, but I don't know about such a PCIe card.
Is there such hardware?
What do you do to avoid this problem?With regards,
Paul van der Vlis.--
Paul van der Vlis Linux systeembeheer, Groningen
http://www.vandervlis.nl/--
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Signature · 2 lines
Paul van der Vlis Linux systeembeheer, Groningen http://www.vandervlis.nl/
I have found placing /boot + MBR on a DOM (Disk on module) to be very effective.
Perhaps we should be asking how the MBR got broken in the first place?
Quoted 71 lines · Paul van der Vlis
Hi Roberto,
op 29-08-14 22:44, Roberto Spadim schreef:
Quoted 2 lines
i use two or more boot disks, if the first raid1 disk don't boot bios go to second boot disk, third, etc etc,
In my opinion this only works when the boot-disk is completely defect or removed. Not when the data in the MBR on that boot-disk is corrupt.
Or did you test this, or do you have other reasons to believe that your bios will handle this correct?
With the boot-disk I mean the disk what's in the bios the first disk. So this could also be the second raid1 disk. Or an USB stick.
Quoted 1 line
you must write grub to mbr of each disk
Of course.
With regards,
Paul van der Vlis.Quoted 36 lines
i'm using dell server r410 if i'm not wrong
2014-08-29 17:31 GMT-03:00 Paul van der Vlis <[email protected]>:
Quoted 30 lines
Hello,
I like mdadm and I am using it many years. But in my opinion it has one
disadvantage: when the MBR of the boot-disk is corrupt, the machine will not boot.A bios could check this. Wait for some kind of signal from Grub or Linux, and after a timeout boot from another disk. But I don't know about a bios with that feature.
A PCIe card could do something like that, but I don't know about such a PCIe card.
Is there such hardware?
What do you do to avoid this problem?With regards,
Paul van der Vlis.--
Paul van der Vlis Linux systeembeheer, Groningen
http://www.vandervlis.nl/--
To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to [email protected]
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http://www.vandervlis.nl/--
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op 29-08-14 23:52, Adam Talbot schreef:
Quoted 2 lines
I have found placing /boot + MBR on a DOM (Disk on module) to be very effective.
Maybe a good DOM is more reliable then a good harddisk. But it's not redundant.
Quoted 1 line
Perhaps we should be asking how the MBR got broken in the first place?
I am using mdadm about 12 years, and I've seen many times that a system did not come up after booting. And when I removed the boot-disk, it did come up.
I must say it's less then for a few years, maybe I am using better disks. But I am looking for something what's better.
What helps, is that there is something like IPMI. So when there is a problem and IPMI is working fine, you can boot by hand from another disk.
With regards,
Paul van der Vlis.
Quoted 77 lines · Paul van der Vlis
Quoted 63 lines
Hi Roberto,
op 29-08-14 22:44, Roberto Spadim schreef:
Quoted 2 lines
i use two or more boot disks, if the first raid1 disk don't boot bios go to second boot disk, third, etc etc,
In my opinion this only works when the boot-disk is completely defect or removed. Not when the data in the MBR on that boot-disk is corrupt.
Or did you test this, or do you have other reasons to believe that your bios will handle this correct?
With the boot-disk I mean the disk what's in the bios the first disk. So this could also be the second raid1 disk. Or an USB stick.
Quoted 1 line
you must write grub to mbr of each disk
Of course.
With regards,
Paul van der Vlis.Quoted 36 lines
i'm using dell server r410 if i'm not wrong
2014-08-29 17:31 GMT-03:00 Paul van der Vlis <[email protected]>:
Quoted 30 lines
Hello,
I like mdadm and I am using it many years. But in my opinion it has one
disadvantage: when the MBR of the boot-disk is corrupt, the machine will not boot.A bios could check this. Wait for some kind of signal from Grub or Linux, and after a timeout boot from another disk. But I don't know about a bios with that feature.
A PCIe card could do something like that, but I don't know about such a PCIe card.
Is there such hardware?
What do you do to avoid this problem?With regards,
Paul van der Vlis.--
Paul van der Vlis Linux systeembeheer, Groningen
http://www.vandervlis.nl/--
To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.htmlQuoted 8 lines
--
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http://www.vandervlis.nl/--
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Signature · 2 lines
Paul van der Vlis Linux systeembeheer, Groningen http://www.vandervlis.nl/
No bios I have seen automatically handles it unless the disks are total dead, some of the hardware raid controlers may properly deal with a disk returning an error and go to the other mirror, the low end quality raid controllers start around $200.
Outside of the raid controllers I don't believe any of the bioses themselves will do it, so you are unlikely to find any hardware that does that.
Likely he is talking about putting the boot block on multiple disks and and use the bbr menu or the bios boot disk selection to pick another disk.
Quoted 71 lines · Paul van der Vlis
Hi Roberto,
op 29-08-14 22:44, Roberto Spadim schreef:
Quoted 2 lines
i use two or more boot disks, if the first raid1 disk don't boot bios go to second boot disk, third, etc etc,
In my opinion this only works when the boot-disk is completely defect or removed. Not when the data in the MBR on that boot-disk is corrupt.
Or did you test this, or do you have other reasons to believe that your bios will handle this correct?
With the boot-disk I mean the disk what's in the bios the first disk. So this could also be the second raid1 disk. Or an USB stick.
Quoted 1 line
you must write grub to mbr of each disk
Of course.
With regards,
Paul van der Vlis.Quoted 36 lines
i'm using dell server r410 if i'm not wrong
2014-08-29 17:31 GMT-03:00 Paul van der Vlis <[email protected]>:
Quoted 30 lines
Hello,
I like mdadm and I am using it many years. But in my opinion it has one
disadvantage: when the MBR of the boot-disk is corrupt, the machine will not boot.A bios could check this. Wait for some kind of signal from Grub or Linux, and after a timeout boot from another disk. But I don't know about a bios with that feature.
A PCIe card could do something like that, but I don't know about such a PCIe card.
Is there such hardware?
What do you do to avoid this problem?With regards,
Paul van der Vlis.--
Paul van der Vlis Linux systeembeheer, Groningen
http://www.vandervlis.nl/--
To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html--
Paul van der Vlis Linux systeembeheer, Groningen
http://www.vandervlis.nl/--
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op 30-08-14 00:38, Roger Heflin schreef:
Quoted 2 lines
No bios I have seen automatically handles it unless the disks are total dead,
That's my experience too.
Quoted 3 lines
some of the hardware raid controlers may properly deal
with a disk returning an error and go to the other mirror, the low end quality raid controllers start around $200.
Hardware raid controllers have other disadvantages, like using a proprietary format for storing information on disk. And in many cases you have to use tools from the manufacturer. That are reasons for me to like mdadm.
Maybe it could be done with a hardware raid controller in JBOD mode.
( And hardware controllers are not perfect too, I've seen simular problems with an HP smart array. First when I've removed the first harddisk the system did boot from the second. )
Quoted 3 lines
Outside of the raid controllers I don't believe any of the bioses themselves will do it, so you are unlikely to find any hardware that does that.
It could be done with a PCIe card too. Some kind of fake-raid adapter what uses mdadm.
Quoted 3 lines
Likely he is talking about putting the boot block on multiple disks and and use the bbr menu or the bios boot disk selection to pick another disk.
Not sure what a "bbr menu" is. But realize that the servers I use are remote.
With regards,
Paul van der Vlis.
Quoted 77 lines · Paul van der Vlis
Quoted 63 lines
Hi Roberto,
op 29-08-14 22:44, Roberto Spadim schreef:
Quoted 2 lines
i use two or more boot disks, if the first raid1 disk don't boot bios go to second boot disk, third, etc etc,
In my opinion this only works when the boot-disk is completely defect or removed. Not when the data in the MBR on that boot-disk is corrupt.
Or did you test this, or do you have other reasons to believe that your bios will handle this correct?
With the boot-disk I mean the disk what's in the bios the first disk. So this could also be the second raid1 disk. Or an USB stick.
Quoted 1 line
you must write grub to mbr of each disk
Of course.
With regards,
Paul van der Vlis.Quoted 36 lines
i'm using dell server r410 if i'm not wrong
2014-08-29 17:31 GMT-03:00 Paul van der Vlis <[email protected]>:
Quoted 30 lines
Hello,
I like mdadm and I am using it many years. But in my opinion it has one
disadvantage: when the MBR of the boot-disk is corrupt, the machine will not boot.A bios could check this. Wait for some kind of signal from Grub or Linux, and after a timeout boot from another disk. But I don't know about a bios with that feature.
A PCIe card could do something like that, but I don't know about such a PCIe card.
Is there such hardware?
What do you do to avoid this problem?With regards,
Paul van der Vlis.--
Paul van der Vlis Linux systeembeheer, Groningen
http://www.vandervlis.nl/--
To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.htmlQuoted 8 lines
--
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http://www.vandervlis.nl/--
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Signature · 2 lines
Paul van der Vlis Linux systeembeheer, Groningen http://www.vandervlis.nl/
That means you need an external config tool (serial, ilo or IMM that allows remote console access), I rarely go into the data center that all of the hw I run is in, and because of the remote console access can fix all but truly broken hw without having hands in the DC). For most low end enterprise hw this option adds $200-300 to the price.
If using the simplest (serial) the given mb bios must support
serial and all add-on bioses must also properly support serial. I
have messed with machines that when using serial you cannot see/access
some of the add on bioses which limits what you can do. ILO/IMM
(full graphics console remote type setups) don't have this deficiency and can in some cases actually allow one to present a remote boot cd to a device and rescue boot it.
The MBR did not get broken, it was broken like this as originally designed 30 years ago, it was always setup to be only able to deal with totally dead drivers (ie drive not showing up at all).
Quoted 128 lines · Paul van der Vlis
op 30-08-14 00:38, Roger Heflin schreef:
Quoted 2 lines
No bios I have seen automatically handles it unless the disks are total dead,
That's my experience too.
Quoted 3 lines
some of the hardware raid controlers may properly deal
with a disk returning an error and go to the other mirror, the low end quality raid controllers start around $200.Hardware raid controllers have other disadvantages, like using a proprietary format for storing information on disk. And in many cases you have to use tools from the manufacturer. That are reasons for me to like mdadm.
Maybe it could be done with a hardware raid controller in JBOD mode.
( And hardware controllers are not perfect too, I've seen simular problems with an HP smart array. First when I've removed the first harddisk the system did boot from the second. )
Quoted 3 lines
Outside of the raid controllers I don't believe any of the bioses themselves will do it, so you are unlikely to find any hardware that does that.
It could be done with a PCIe card too. Some kind of fake-raid adapter what uses mdadm.
Quoted 3 lines
Likely he is talking about putting the boot block on multiple disks and and use the bbr menu or the bios boot disk selection to pick another disk.
Not sure what a "bbr menu" is. But realize that the servers I use are remote.
With regards,
Paul van der Vlis.Quoted 68 lines · Paul van der Vlis
Quoted 67 lines
Hi Roberto,
op 29-08-14 22:44, Roberto Spadim schreef:
Quoted 2 lines
i use two or more boot disks, if the first raid1 disk don't boot bios go to second boot disk, third, etc etc,
In my opinion this only works when the boot-disk is completely defect or removed. Not when the data in the MBR on that boot-disk is corrupt.
Or did you test this, or do you have other reasons to believe that your bios will handle this correct?
With the boot-disk I mean the disk what's in the bios the first disk. So this could also be the second raid1 disk. Or an USB stick.
Quoted 1 line
you must write grub to mbr of each disk
Of course.
With regards,
Paul van der Vlis.Quoted 36 lines
i'm using dell server r410 if i'm not wrong
2014-08-29 17:31 GMT-03:00 Paul van der Vlis <[email protected]>:
Quoted 30 lines
Hello,
I like mdadm and I am using it many years. But in my opinion it has one
disadvantage: when the MBR of the boot-disk is corrupt, the machine will not boot.A bios could check this. Wait for some kind of signal from Grub or Linux, and after a timeout boot from another disk. But I don't know about a bios with that feature.
A PCIe card could do something like that, but I don't know about such a PCIe card.
Is there such hardware?
What do you do to avoid this problem?With regards,
Paul van der Vlis.--
Paul van der Vlis Linux systeembeheer, Groningen
http://www.vandervlis.nl/--
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Paul van der Vlis Linux systeembeheer, Groningen
http://www.vandervlis.nl/Quoted 9 lines
Quoted 4 lines
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op 30-08-14 11:53, Roger Heflin schreef:
Quoted 4 lines
That means you need an external config tool (serial, ilo or IMM that allows remote console access), I rarely go into the data center that all of the hw I run is in, and because of the remote console access can fix all but truly broken hw without having hands in the DC).
That's a way to repear something what's broken. Not a more redundant solution I was looking for. But you are right, it helps a lot. I use IPMI for remote console. And on some machines a serial console.
What I don't like about IPMI is that the part on the server is -so far I know- not really open source and I cannot update it for security, so I can only use it from a secure subnet initiated by another machine.
A serial connection can be done OSS, but you need another machine in the direct neighborhood, and it's not really nice.
So in both cases you need 2 machines with at least to IP's. Many firms here have DSL with only one IP.
Quoted 1 line
For most low end enterprise hw this option adds $200-300 to the price.
It's standard on the machines I buy (Supermicro).
Quoted 7 lines
If using the simplest (serial) the given mb bios must support
serial and all add-on bioses must also properly support serial. I
have messed with machines that when using serial you cannot see/access
some of the add on bioses which limits what you can do. ILO/IMM
(full graphics console remote type setups) don't have this deficiency and can in some cases actually allow one to present a remote boot cd to a device and rescue boot it.
Not sure this is possible with OSS applications.
Quoted 3 lines
The MBR did not get broken, it was broken like this as originally designed 30 years ago, it was always setup to be only able to deal with totally dead drivers (ie drive not showing up at all).
I think you mean the bios. Some bios-es can do fakeraid, and I expect they can boot from another disk when the first disk is corrupt. But you cannot use mdadm then, what I would like.
With regards,
Paul van der Vlis.
Quoted 134 lines · Paul van der Vlis
Quoted 120 lines
op 30-08-14 00:38, Roger Heflin schreef:
Quoted 2 lines
No bios I have seen automatically handles it unless the disks are total dead,
That's my experience too.
Quoted 3 lines
some of the hardware raid controlers may properly deal
with a disk returning an error and go to the other mirror, the low end quality raid controllers start around $200.Hardware raid controllers have other disadvantages, like using a proprietary format for storing information on disk. And in many cases you have to use tools from the manufacturer. That are reasons for me to like mdadm.
Maybe it could be done with a hardware raid controller in JBOD mode.
( And hardware controllers are not perfect too, I've seen simular problems with an HP smart array. First when I've removed the first harddisk the system did boot from the second. )
Quoted 3 lines
Outside of the raid controllers I don't believe any of the bioses themselves will do it, so you are unlikely to find any hardware that does that.
It could be done with a PCIe card too. Some kind of fake-raid adapter what uses mdadm.
Quoted 3 lines
Likely he is talking about putting the boot block on multiple disks and and use the bbr menu or the bios boot disk selection to pick another disk.
Not sure what a "bbr menu" is. But realize that the servers I use are remote.
With regards,
Paul van der Vlis.Quoted 68 lines · Paul van der Vlis
Quoted 67 lines
Hi Roberto,
op 29-08-14 22:44, Roberto Spadim schreef:
Quoted 2 lines
i use two or more boot disks, if the first raid1 disk don't boot bios go to second boot disk, third, etc etc,
In my opinion this only works when the boot-disk is completely defect or removed. Not when the data in the MBR on that boot-disk is corrupt.
Or did you test this, or do you have other reasons to believe that your bios will handle this correct?
With the boot-disk I mean the disk what's in the bios the first disk. So this could also be the second raid1 disk. Or an USB stick.
Quoted 1 line
you must write grub to mbr of each disk
Of course.
With regards,
Paul van der Vlis.Quoted 36 lines
i'm using dell server r410 if i'm not wrong
2014-08-29 17:31 GMT-03:00 Paul van der Vlis <[email protected]>:
Quoted 30 lines
Hello,
I like mdadm and I am using it many years. But in my opinion it has one
disadvantage: when the MBR of the boot-disk is corrupt, the machine will not boot.A bios could check this. Wait for some kind of signal from Grub or Linux, and after a timeout boot from another disk. But I don't know about a bios with that feature.
A PCIe card could do something like that, but I don't know about such a PCIe card.
Is there such hardware?
What do you do to avoid this problem?With regards,
Paul van der Vlis.--
Paul van der Vlis Linux systeembeheer, Groningen
http://www.vandervlis.nl/--
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Paul van der Vlis Linux systeembeheer, Groningen
http://www.vandervlis.nl/Quoted 9 lines
Quoted 4 lines
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More majordomo info at http://vger.kernel.org/majordomo-info.htmlQuoted 8 lines
--
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Signature · 2 lines
Paul van der Vlis Linux systeembeheer, Groningen http://www.vandervlis.nl/
Quoted 10 lines · Paul van der Vlis
op 30-08-14 11:53, Roger Heflin schreef:
Quoted 4 lines
That means you need an external config tool (serial, ilo or IMM that allows remote console access), I rarely go into the data center that all of the hw I run is in, and because of the remote console access can fix all but truly broken hw without having hands in the DC).
That's a way to repear something what's broken. Not a more redundant solution I was looking for. But you are right, it helps a lot. I use IPMI for remote console. And on some machines a serial console.
You do realise that the IPMI is also not redundant and uses exactly the same memory type that the DOM offers (which you pointed out was not redundant).
Disks die. Anything else is a hands on fix. If you want more reliable you go dual-redundant (possibly with a hot standby).
Regards,
Brad
Signature · 3 lines
Dolphins are so intelligent that within a few weeks they can train Americans to stand at the edge of the pool and throw them fish.
i'm considering that you are using x86, x86_64 hardware, what's your application?
there's no bios test (must check if the newer version of this server have uefi and work differente), it just don't boot the disk and go to next boot
but for your question: yes... maybe with 'lucky' it can't boot, a "bad" (crashed) grub could stop server startup
maybe others questions that you could check before solving this boot problem is why use a "bad" disk?
why shutdown a server?
why remote startup a server?
why use a 'bad' disk?
if it's a ha system, include a human to check monthly, or something like it, if the server is ok clean,something like it, since ha probably include a real time application or a security or risk application, or anything like it
probably you must check others solutions at hardware level, some computers have dual bios (yes if one bios is lost you have the other to boot the computer), maybe an openbios could help, or a uefi bios, must check what's better
2014-08-29 18:47 GMT-03:00 Paul van der Vlis <[email protected]>:
Quoted 71 lines
Hi Roberto,
op 29-08-14 22:44, Roberto Spadim schreef:
Quoted 2 lines
i use two or more boot disks, if the first raid1 disk don't boot bios go to second boot disk, third, etc etc,
In my opinion this only works when the boot-disk is completely defect or removed. Not when the data in the MBR on that boot-disk is corrupt.
Or did you test this, or do you have other reasons to believe that your bios will handle this correct?
With the boot-disk I mean the disk what's in the bios the first disk. So this could also be the second raid1 disk. Or an USB stick.
Quoted 1 line
you must write grub to mbr of each disk
Of course.
With regards,
Paul van der Vlis.Quoted 36 lines
i'm using dell server r410 if i'm not wrong
2014-08-29 17:31 GMT-03:00 Paul van der Vlis <[email protected]>:
Quoted 30 lines
Hello,
I like mdadm and I am using it many years. But in my opinion it has one
disadvantage: when the MBR of the boot-disk is corrupt, the machine will not boot.A bios could check this. Wait for some kind of signal from Grub or Linux, and after a timeout boot from another disk. But I don't know about a bios with that feature.
A PCIe card could do something like that, but I don't know about such a PCIe card.
Is there such hardware?
What do you do to avoid this problem?With regards,
Paul van der Vlis.--
Paul van der Vlis Linux systeembeheer, Groningen
http://www.vandervlis.nl/--
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Paul van der Vlis Linux systeembeheer, Groningen
http://www.vandervlis.nl/--
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Roberto Spadim
op 30-08-14 02:44, Roberto Spadim schreef:
Quoted 2 lines
i'm considering that you are using x86,
x86_64hardware, what's your application?
I am a sysadmin and I administrate many machines: webservers and mailservers located in a datacenter, fileservers located at firms, etc.
Quoted 8 lines
there's no bios test (must check if the newer version of this server have uefi and work differente), it just don't boot the disk and go to next boot
but for your question: yes... maybe with 'lucky' it can't boot, a "bad" (crashed) grub could stop server startupmaybe others questions that you could check before solving this boot problem is why use a "bad" disk?
I would replace it when I would know it's bad.
Quoted 1 line
why shutdown a server?
Kernel updates.
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why remote startup a server?
Because it's work to go to such a location.
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why use a 'bad' disk?
I would replace it when I would know it's bad.
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if it's a ha system,
Not really. Maybe.
Quoted 2 lines
include a human to check monthly, or something like it, if the server is ok clean,something like it,
You can't check that way if a MBR boots.
Quoted 3 lines
since ha
probably include a real time application or a security or risk application, or anything like it
I don't know about such an application. But maybe it would be possible to read the MBR and check it with a copy. I was looking for a redundant solution, maybe I must forget that.
Quoted 3 lines
probably you must check others solutions at hardware level, some computers have dual bios (yes if one bios is lost you have the other to boot the computer),
That's not the problem. I did not see often problems with a bad bios on a good-running system.
Quoted 1 line
maybe an openbios could help
It's difficult to buy hardware for coreboot. And I don't think coreboot can check the booting process.
Quoted 1 line
, or a uefi bios, must check what's better
Do you know about UEFI bios-es who can check the process?
With regards,
Paul van der Vlis.
Quoted 77 lines
2014-08-29 18:47 GMT-03:00 Paul van der Vlis <[email protected]>:
Quoted 71 lines
Hi Roberto,
op 29-08-14 22:44, Roberto Spadim schreef:
Quoted 2 lines
i use two or more boot disks, if the first raid1 disk don't boot bios go to second boot disk, third, etc etc,
In my opinion this only works when the boot-disk is completely defect or removed. Not when the data in the MBR on that boot-disk is corrupt.
Or did you test this, or do you have other reasons to believe that your bios will handle this correct?
With the boot-disk I mean the disk what's in the bios the first disk. So this could also be the second raid1 disk. Or an USB stick.
Quoted 1 line
you must write grub to mbr of each disk
Of course.
With regards,
Paul van der Vlis.Quoted 36 lines
i'm using dell server r410 if i'm not wrong
2014-08-29 17:31 GMT-03:00 Paul van der Vlis <[email protected]>:
Quoted 30 lines
Hello,
I like mdadm and I am using it many years. But in my opinion it has one
disadvantage: when the MBR of the boot-disk is corrupt, the machine will not boot.A bios could check this. Wait for some kind of signal from Grub or Linux, and after a timeout boot from another disk. But I don't know about a bios with that feature.
A PCIe card could do something like that, but I don't know about such a PCIe card.
Is there such hardware?
What do you do to avoid this problem?With regards,
Paul van der Vlis.--
Paul van der Vlis Linux systeembeheer, Groningen
http://www.vandervlis.nl/--
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Paul van der Vlis Linux systeembeheer, Groningen
http://www.vandervlis.nl/--
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Paul van der Vlis Linux systeembeheer, Groningen http://www.vandervlis.nl/