From 36fa139a44c38d8c0655fb076e90dd64d1cbfcd5 Mon Sep 17 00:00:00 2001 From: Holger Wansing Date: Sun, 11 Aug 2019 15:24:22 +0200 Subject: Rename mdcfg into partman-md and lvmcfg into partman-lvm --- en/using-d-i/components.xml | 2 +- en/using-d-i/modules/mdcfg.xml | 300 ------------------------------------ en/using-d-i/modules/partman-md.xml | 300 ++++++++++++++++++++++++++++++++++++ en/using-d-i/using-d-i.xml | 4 +- 4 files changed, 303 insertions(+), 303 deletions(-) delete mode 100644 en/using-d-i/modules/mdcfg.xml create mode 100644 en/using-d-i/modules/partman-md.xml (limited to 'en/using-d-i') diff --git a/en/using-d-i/components.xml b/en/using-d-i/components.xml index c7e5e8bad..e1f915c18 100644 --- a/en/using-d-i/components.xml +++ b/en/using-d-i/components.xml @@ -97,7 +97,7 @@ like RAID, LVM or encrypted devices. &module-autopartkit.xml; &module-partitioner.xml; &module-partconf.xml; -&module-mdcfg.xml; +&module-partman-md.xml; &module-partman-lvm.xml; &module-partman-crypto.xml; diff --git a/en/using-d-i/modules/mdcfg.xml b/en/using-d-i/modules/mdcfg.xml deleted file mode 100644 index 8d2854ff3..000000000 --- a/en/using-d-i/modules/mdcfg.xml +++ /dev/null @@ -1,300 +0,0 @@ - - - - - Configuring Multidisk Devices (Software RAID) - - -If you have more than one harddrive - -To be honest, you can construct an MD device even from partitions -residing on single physical drive, but that won't give any benefits. - - in your computer, you can use -mdcfg to set up your drives for increased -performance and/or better reliability of your data. The result is -called Multidisk Device (or after its most -famous variant software RAID). - - - -MD is basically a bunch of partitions located on different disks and -combined together to form a logical device. This -device can then be used like an ordinary partition (i.e. in -partman you can format it, assign a mountpoint, -etc.). - - - -What benefits this brings depends on the type of MD device you are -creating. Currently supported are: - - - - -RAID0 - -Is mainly aimed at performance. RAID0 splits all incoming data into -stripes and distributes them equally over each -disk in the array. This can increase the speed of read/write -operations, but when one of the disks fails, you will lose -everything (part of the information is still on -the healthy disk(s), the other part was on the -failed disk). - - - -The typical use for RAID0 is a partition for video editing. - - - - - -RAID1 - -Is suitable for setups where reliability is the first concern. It -consists of several (usually two) equally-sized partitions where every -partition contains exactly the same data. This essentially means three -things. First, if one of your disks fails, you still have the data -mirrored on the remaining disks. Second, you can use only a fraction -of the available capacity (more precisely, it is the size of the -smallest partition in the RAID). Third, file-reads are load-balanced among -the disks, which can improve performance on a server, such as a file -server, that tends to be loaded with more disk reads than writes. - - - -Optionally you can have a spare disk in the array which will take the -place of the failed disk in the case of failure. - - - - - -RAID5 - -Is a good compromise between speed, reliability and data redundancy. -RAID5 splits all incoming data into stripes and distributes them -equally on all but one disk (similar to RAID0). Unlike RAID0, RAID5 -also computes parity information, which gets -written on the remaining disk. The parity disk is not static (that -would be called RAID4), but is changing periodically, so the parity -information is distributed equally on all disks. When one of the -disks fails, the missing part of information can be computed from -remaining data and its parity. RAID5 must consist of at least three -active partitions. Optionally you can have a spare disk in the array -which will take the place of the failed disk in the case of failure. - - - -As you can see, RAID5 has a similar degree of reliability to RAID1 -while achieving less redundancy. On the other hand, it might be a bit -slower on write operations than RAID0 due to computation of parity -information. - - - - - -RAID6 - -Is similar to RAID5 except that it uses two parity devices instead of -one. - - - -A RAID6 array can survive up to two disk failures. - - - - - -RAID10 - -RAID10 combines striping (as in RAID0) and mirroring (as in RAID1). -It creates n copies of incoming data and -distributes them across the partitions so that none of the copies of -the same data are on the same device. -The default value of n is 2, but it can be -set to something else in expert mode. The number of partitions used -must be at least n. -RAID10 has different layouts for distributing the copies. The default is -near copies. Near copies have all of the copies at about the same offset -on all of the disks. Far copies have the copies at different offsets on -the disks. Offset copies copy the stripe, not the individual copies. - - - -RAID10 can be used to achieve reliability and redundancy without the -drawback of having to calculate parity. - - - - - -To sum it up: - - - - - - Type - Minimum Devices - Spare Device - Survives disk failure? - Available Space - - - - - - RAID0 - 2 - no - no - Size of the smallest partition multiplied by number of devices in RAID - - - - RAID1 - 2 - optional - yes - Size of the smallest partition in RAID - - - - RAID5 - 3 - optional - yes - - Size of the smallest partition multiplied by (number of devices in - RAID minus one) - - - - - RAID6 - 4 - optional - yes - - Size of the smallest partition multiplied by (number of devices in - RAID minus two) - - - - - RAID10 - 2 - optional - yes - - Total of all partitions divided by the number of chunk copies (defaults to two) - - - - - - - -If you want to know more about Software RAID, have a look -at Software RAID HOWTO. - - - -To create an MD device, you need to have the desired partitions it -should consist of marked for use in a RAID. (This is done in -partman in the Partition -settings menu where you should select -Use as: physical volume for -RAID .) - - - -Make sure that the system can be booted with the partitioning scheme -you are planning. In general it will be necessary to create a separate -file system for /boot when using RAID for the root -(/) file system. -Most boot loaders (including lilo and grub) -do support mirrored (not striped!) RAID1, so using for example RAID5 for -/ and RAID1 for /boot can be -an option. - - - -Next, you should choose Configure software -RAID from the main partman menu. -(The menu will only appear after you mark at least one partition for -use as physical volume for RAID.) -On the first screen of mdcfg simply select -Create MD device. You will be presented with -a list of supported types of MD devices, from which you should choose -one (e.g. RAID1). What follows depends on the type of MD you selected. - - - - - -RAID0 is simple — you will be issued with the list of available -RAID partitions and your only task is to select the partitions which -will form the MD. - - - - -RAID1 is a bit more tricky. First, you will be asked to enter the -number of active devices and the number of spare devices which will -form the MD. Next, you need to select from the list of available RAID -partitions those that will be active and then those that will be -spare. The count of selected partitions must be equal to the number -provided earlier. Don't worry. If you make a mistake and -select a different number of partitions, &d-i; won't let you -continue until you correct the issue. - - - - -RAID5 has a setup procedure similar to RAID1 with the exception that you -need to use at least three active partitions. - - - - -RAID6 also has a setup procedure similar to RAID1 except that at least -four active partitions are required. - - - - -RAID10 again has a setup procedure similar to RAID1 except in expert -mode. In expert mode, &d-i; will ask you for the layout. -The layout has two parts. The first part is the layout type. It is either -n (for near copies), f (for far -copies), or o (for offset copies). The second part is -the number of copies to make of the data. There must be at least that -many active devices so that all of the copies can be distributed onto -different disks. - - - - - - -It is perfectly possible to have several types of MD at once. For -example, if you have three 200 GB hard drives dedicated to MD, each -containing two 100 GB partitions, you can combine the first partitions on -all three disks into the RAID0 (fast 300 GB video editing partition) -and use the other three partitions (2 active and 1 spare) for RAID1 -(quite reliable 100 GB partition for /home). - - - -After you set up MD devices to your liking, you can -Finish mdcfg to return -back to the partman to create filesystems on your -new MD devices and assign them the usual attributes like mountpoints. - - - diff --git a/en/using-d-i/modules/partman-md.xml b/en/using-d-i/modules/partman-md.xml new file mode 100644 index 000000000..9dffad9f8 --- /dev/null +++ b/en/using-d-i/modules/partman-md.xml @@ -0,0 +1,300 @@ + + + + + Configuring Multidisk Devices (Software RAID) + + +If you have more than one harddrive + +To be honest, you can construct an MD device even from partitions +residing on single physical drive, but that won't give any benefits. + + in your computer, you can use +partman-md to set up your drives for increased +performance and/or better reliability of your data. The result is +called Multidisk Device (or after its most +famous variant software RAID). + + + +MD is basically a bunch of partitions located on different disks and +combined together to form a logical device. This +device can then be used like an ordinary partition (i.e. in +partman you can format it, assign a mountpoint, +etc.). + + + +What benefits this brings depends on the type of MD device you are +creating. Currently supported are: + + + + +RAID0 + +Is mainly aimed at performance. RAID0 splits all incoming data into +stripes and distributes them equally over each +disk in the array. This can increase the speed of read/write +operations, but when one of the disks fails, you will lose +everything (part of the information is still on +the healthy disk(s), the other part was on the +failed disk). + + + +The typical use for RAID0 is a partition for video editing. + + + + + +RAID1 + +Is suitable for setups where reliability is the first concern. It +consists of several (usually two) equally-sized partitions where every +partition contains exactly the same data. This essentially means three +things. First, if one of your disks fails, you still have the data +mirrored on the remaining disks. Second, you can use only a fraction +of the available capacity (more precisely, it is the size of the +smallest partition in the RAID). Third, file-reads are load-balanced among +the disks, which can improve performance on a server, such as a file +server, that tends to be loaded with more disk reads than writes. + + + +Optionally you can have a spare disk in the array which will take the +place of the failed disk in the case of failure. + + + + + +RAID5 + +Is a good compromise between speed, reliability and data redundancy. +RAID5 splits all incoming data into stripes and distributes them +equally on all but one disk (similar to RAID0). Unlike RAID0, RAID5 +also computes parity information, which gets +written on the remaining disk. The parity disk is not static (that +would be called RAID4), but is changing periodically, so the parity +information is distributed equally on all disks. When one of the +disks fails, the missing part of information can be computed from +remaining data and its parity. RAID5 must consist of at least three +active partitions. Optionally you can have a spare disk in the array +which will take the place of the failed disk in the case of failure. + + + +As you can see, RAID5 has a similar degree of reliability to RAID1 +while achieving less redundancy. On the other hand, it might be a bit +slower on write operations than RAID0 due to computation of parity +information. + + + + + +RAID6 + +Is similar to RAID5 except that it uses two parity devices instead of +one. + + + +A RAID6 array can survive up to two disk failures. + + + + + +RAID10 + +RAID10 combines striping (as in RAID0) and mirroring (as in RAID1). +It creates n copies of incoming data and +distributes them across the partitions so that none of the copies of +the same data are on the same device. +The default value of n is 2, but it can be +set to something else in expert mode. The number of partitions used +must be at least n. +RAID10 has different layouts for distributing the copies. The default is +near copies. Near copies have all of the copies at about the same offset +on all of the disks. Far copies have the copies at different offsets on +the disks. Offset copies copy the stripe, not the individual copies. + + + +RAID10 can be used to achieve reliability and redundancy without the +drawback of having to calculate parity. + + + + + +To sum it up: + + + + + + Type + Minimum Devices + Spare Device + Survives disk failure? + Available Space + + + + + + RAID0 + 2 + no + no + Size of the smallest partition multiplied by number of devices in RAID + + + + RAID1 + 2 + optional + yes + Size of the smallest partition in RAID + + + + RAID5 + 3 + optional + yes + + Size of the smallest partition multiplied by (number of devices in + RAID minus one) + + + + + RAID6 + 4 + optional + yes + + Size of the smallest partition multiplied by (number of devices in + RAID minus two) + + + + + RAID10 + 2 + optional + yes + + Total of all partitions divided by the number of chunk copies (defaults to two) + + + + + + + +If you want to know more about Software RAID, have a look +at Software RAID HOWTO. + + + +To create an MD device, you need to have the desired partitions it +should consist of marked for use in a RAID. (This is done in +partman in the Partition +settings menu where you should select +Use as: physical volume for +RAID .) + + + +Make sure that the system can be booted with the partitioning scheme +you are planning. In general it will be necessary to create a separate +file system for /boot when using RAID for the root +(/) file system. +Most boot loaders (including lilo and grub) +do support mirrored (not striped!) RAID1, so using for example RAID5 for +/ and RAID1 for /boot can be +an option. + + + +Next, you should choose Configure software +RAID from the main partman menu. +(The menu will only appear after you mark at least one partition for +use as physical volume for RAID.) +On the first screen of partman-md simply select +Create MD device. You will be presented with +a list of supported types of MD devices, from which you should choose +one (e.g. RAID1). What follows depends on the type of MD you selected. + + + + + +RAID0 is simple — you will be issued with the list of available +RAID partitions and your only task is to select the partitions which +will form the MD. + + + + +RAID1 is a bit more tricky. First, you will be asked to enter the +number of active devices and the number of spare devices which will +form the MD. Next, you need to select from the list of available RAID +partitions those that will be active and then those that will be +spare. The count of selected partitions must be equal to the number +provided earlier. Don't worry. If you make a mistake and +select a different number of partitions, &d-i; won't let you +continue until you correct the issue. + + + + +RAID5 has a setup procedure similar to RAID1 with the exception that you +need to use at least three active partitions. + + + + +RAID6 also has a setup procedure similar to RAID1 except that at least +four active partitions are required. + + + + +RAID10 again has a setup procedure similar to RAID1 except in expert +mode. In expert mode, &d-i; will ask you for the layout. +The layout has two parts. The first part is the layout type. It is either +n (for near copies), f (for far +copies), or o (for offset copies). The second part is +the number of copies to make of the data. There must be at least that +many active devices so that all of the copies can be distributed onto +different disks. + + + + + + +It is perfectly possible to have several types of MD at once. For +example, if you have three 200 GB hard drives dedicated to MD, each +containing two 100 GB partitions, you can combine the first partitions on +all three disks into the RAID0 (fast 300 GB video editing partition) +and use the other three partitions (2 active and 1 spare) for RAID1 +(quite reliable 100 GB partition for /home). + + + +After you set up MD devices to your liking, you can +Finish partman-md to return +back to the partman to create filesystems on your +new MD devices and assign them the usual attributes like mountpoints. + + + diff --git a/en/using-d-i/using-d-i.xml b/en/using-d-i/using-d-i.xml index a52e0e952..56091b6e1 100644 --- a/en/using-d-i/using-d-i.xml +++ b/en/using-d-i/using-d-i.xml @@ -345,7 +345,7 @@ the selected partitions according to user instructions. -lvmcfg +partman-lvm Helps the user with the configuration of the LVM (Logical Volume Manager). @@ -354,7 +354,7 @@ Helps the user with the configuration of the -mdcfg +partman-md Allows the user to set up Software RAID (Redundant Array of Inexpensive Disks). This Software RAID is usually -- cgit v1.2.3