Divide partition on the drive the place OS X used to reside into two partitions of equal measurement. Usually, the Disk Utility or diskutil command can be used to make the adjustments. Nonetheless, since you might be booted from the restoration quantity on the identical drive, neither the Disk Utility or diskutil command can be utilized to efficiently make the adjustments. The process given on this step does use the diskutil command, however to not make adjustments to the this drive. Different instructions are used to make the adjustments.
Begin by enter the command beneath to get a listing of partitions.
diskutil listing disk0
Beneath is the output from my check surroundings. I assume you’ll get related output with completely different sizes.
-bash-3.2# diskutil listing disk0
/dev/disk0
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme +268.4 GB disk0
1: EFI EFI 209.7 MB disk0s1
2: Apple_HFS Macintosh HD 267.6 GB disk0s2
3: Apple_Boot Restoration HD 650.0 MB disk0s3
For this process to work, the Macintosh HD quantity (disk0s2) must be changed by two volumes of equal measurement. Finally, one of many volumes will probably be transformed to free area and the opposite will probably be develop to fill this free area. To find out the dimensions of the 2 new volumes, the next command must be entered to get the sizes pertaining to the present quantity.
diskutil information disk0s2 | grep Dimension
Beneath is my output from coming into the above command.
-bash-3.2# diskutil information disk0s2 | grep Dimension
Disk Dimension: 267.6 GB (267575697408 Bytes) (precisely 522608784 512-Byte-Items)
Gadget Block Dimension: 512 Bytes
Allocation Block Dimension: 4096 Bytes
The equation beneath can be utilized to compute the dimensions of the brand new partitions in sectors.
Partition Dimension in Sectors = Disk Dimension in 512-Byte-Items/16*(4096/Gadget Block Dimension)
This equation might be evaluated by coming into the command given beneath. You will want to switch the values of 522608784 and 512 along with your values for Disk Dimension in 512-Byte-Items and Gadget Block Dimension, respectively.
echo "Partition Dimension in Sectors = $((522608784/16*(4096/512)))"
Beneath is my output from coming into the above command.
-bash-3.2# echo "Partition Dimension in Sectors = $((522608784/16*(4096/512)))"
Partition Dimension in Sectors = 261304392
These subsequent instructions will forestall the partition (disk0s2) containing the prevailing quantity from mounting. Additionally, the brand new partitions created later will be unable to mount till after being formatted. You will want to switch the values of 261304392 and 512 along with your values for Partition Dimension in Sectors and Gadget Block Dimension, respectively.
diskutil unmount disk0s2
dd if=/dev/zero rely=100 bs=512 of=/dev/disk0s2
dd if=/dev/zero rely=100 bs=512 search=261304392 of=/dev/disk0s2
Beneath is my output from coming into the above instructions.
-bash-3.2# diskutil unmount disk0s2
Quantity Macintosh HD on disk0s2 unmounted
-bash-3.2# dd if=/dev/zero rely=100 bs=512 of=/dev/disk0s2
100+0 information in
100+0 information out
51200 bytes transferred in 0.024378 secs (2100249 bytes/sec)
-bash-3.2# dd if=/dev/zero rely=100 bs=512 search=261304392 of=/dev/disk0s2
100+0 information in
100+0 information out
51200 bytes transferred in 0.050295 secs (1017996 bytes/sec)
Use the gdisk command to divide partition the place OS X used to reside into two partitions of equal measurement. Right here, I assume your EFI partition (/dev/disk0s1) continues to be mounted on /Volumes/EFI. If not, enter the command beneath.
diskutil mount disk0s1
The command beneath can be utilized to execute gdisk.
/Volumes/EFI/gdisk /dev/disk0
The above command is interactive. The desk beneath lists the required entries. The instructions and knowledge should be entered within the order given within the desk.
Observe: Learn every remark and any relevant footnote fastidiously earlier than making an entry.
| Entries for 512 Byte Gadget Block Dimension |
Entries for 4096 Byte Gadget Block Dimension |
Feedback   |
|---|---|---|
x |
x |
Enter the consultants’ menu |
l |
l |
Change the sector alignment worth |
8 |
1 |
New sector alignment worth |
m |
m |
Return to most important menu |
p |
p |
Show primary partition abstract |
d |
d |
Delete a partition |
2 |
2 |
Partiton to delete |
n |
n |
Create a brand new partition |
2 |
2 |
Partition to create†|
409640 |
76806 |
Beginning sector†|
+261304392 |
+32663049 |
Dimension in sectors* |
AF00 |
AF00 |
Hex code for HFS+ partition†|
n |
n |
Create a brand new partition |
4 |
4 |
Partition to create†|
261714032 |
32739855 |
Beginning sector‡ |
+261304392 |
+32663049 |
Dimension in sectors* |
AF00 |
AF00 |
Hex code for HFS+ partition†|
s |
s |
Type partition entries |
p |
p |
Show primary partition abstract |
w |
w |
Write GPT to disk and exit |
y |
y |
Sure proceed to write down and exit |
*It is best to enter the Partition Dimension in Sectors that you simply calculated earilier as a substitute of the worth proven. Observe, the
+character is important and shouldn’t be omitted.†This needs to be the default worth.
‡This needs to be the default worth. Nonetheless, the worth you see is not going to be the identical as proven within the desk. The worth you see would be the new second partition’s beginning sector plus measurement in sectors.
Beneath is my output from utilizing the gdisk command. The default values have been used when applicable.
-bash-3.2# gdisk /dev/disk0
GPT fdisk (gdisk) model 1.0.8
Warning: Units opened with shared lock is not going to have their
partition desk mechanically reloaded!
Partition desk scan:
MBR: protecting
BSD: not current
APM: not current
GPT: current
Discovered legitimate GPT with protecting MBR; utilizing GPT.
Command (? for assist): x
Knowledgeable command (? for assist): l
Enter the sector alignment worth (1-65536, default = 2048): 8
Knowledgeable command (? for assist): m
Command (? for assist): p
Disk /dev/disk0: 524288000 sectors, 250.0 GiB
Sector measurement (logical): 512 bytes
Disk identifier (GUID): D32269E7-0718-4BCC-A2BD-24ACA171AE82
Partition desk holds as much as 128 entries
Fundamental partition desk begins at sector 2 and ends at sector 33
First usable sector is 34, final usable sector is 524287966
Partitions will probably be aligned on 8-sector boundaries
Complete free area is 13 sectors (6.5 KiB)
Quantity Begin (sector) Finish (sector) Dimension Code Identify
1 40 409639 200.0 MiB EF00 EFI System Partition
2 409640 523018423 249.2 GiB AF00 Apple HFS/HFS+
3 523018424 524287959 619.9 MiB AB00 Restoration HD
Command (? for assist): d
Partition quantity (1-3): 2
Command (? for assist): n
Partition quantity (2-128, default 2):
First sector (34-524287966, default = 409640) or {+-}measurement{KMGTP}:
Final sector (409640-523018423, default = 523018423) or {+-}measurement{KMGTP}: +261304392
Present kind is AF00 (Apple HFS/HFS+)
Hex code or GUID (L to indicate codes, Enter = AF00):
Modified kind of partition to 'Apple HFS/HFS+'
Command (? for assist): n
Partition quantity (4-128, default 4):
First sector (34-524287966, default = 261714032) or {+-}measurement{KMGTP}:
Final sector (261714032-523018423, default = 523018423) or {+-}measurement{KMGTP}: +261304392
Present kind is AF00 (Apple HFS/HFS+)
Hex code or GUID (L to indicate codes, Enter = AF00):
Modified kind of partition to 'Apple HFS/HFS+'
Command (? for assist): s
You could have to edit /and so forth/fstab and/or your boot loader configuration!
Command (? for assist): p
Disk /dev/disk0: 524288000 sectors, 250.0 GiB
Sector measurement (logical): 512 bytes
Disk identifier (GUID): D32269E7-0718-4BCC-A2BD-24ACA171AE82
Partition desk holds as much as 128 entries
Fundamental partition desk begins at sector 2 and ends at sector 33
First usable sector is 34, final usable sector is 524287966
Partitions will probably be aligned on 8-sector boundaries
Complete free area is 13 sectors (6.5 KiB)
Quantity Begin (sector) Finish (sector) Dimension Code Identify
1 40 409639 200.0 MiB EF00 EFI System Partition
2 409640 261714031 124.6 GiB AF00 Apple HFS/HFS+
3 261714032 523018423 124.6 GiB AF00 Apple HFS/HFS+
4 523018424 524287959 619.9 MiB AB00 Restoration HD
Command (? for assist): w
Ultimate checks full. About to write down GPT knowledge. THIS WILL OVERWRITE EXISTING
PARTITIONS!!
Do you need to proceed? (Y/N): y
OK; writing new GUID partition desk (GPT) to /dev/disk0.
Warning: Units opened with shared lock is not going to have their
partition desk mechanically reloaded!
Warning: The kernel could proceed to make use of previous or deleted partitions.
It is best to reboot or take away the drive.
The operation has accomplished efficiently.
Enter the next command to get the identifiers for the 2 new Apple_HFS kind partitions.
diskutil listing disk0
Beneath is my output from coming into the above command.
Observe: The output continues to be displaying the
Macintosh HDbecause the identify ofdisk0s2. This identify will probably be up to date later, when thediskutilis used to mountdisk0s2.
-bash-3.2# diskutil listing disk0
/dev/disk0
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme +268.4 GB disk0
1: EFI EFI 209.7 MB disk0s1
2: Apple_HFS Macintosh HD 133.8 GB disk0s2
3: Apple_HFS 133.8 GB disk0s5
4: Apple_Boot Restoration HD 650.0 MB disk0s3
Enter the next command to format, mount and listing the 2 new partitions. In case your two new partitions have identifiers which differ from disk0s2 or disk0s5, then make the suitable substitutions.
newfs_hfs -J -v Higher /dev/disk0s2
newfs_hfs -J -v Decrease /dev/disk0s5
diskutil mount disk0s2
diskutil mount disk0s5
diskutil listing disk0
Beneath is my output from coming into the above instructions.
-bash-3.2# newfs_hfs -J -v Higher /dev/disk0s2
Initialized /dev/rdisk0s2 as a 125 GB case-insensitive HFS Plus quantity with a 16384k journal
-bash-3.2# newfs_hfs -J -v Decrease /dev/disk0s5
Initialized /dev/rdisk0s5 as a 125 GB case-insensitive HFS Plus quantity with a 16384k journal
-bash-3.2# diskutil mount disk0s2
Quantity Higher on disk0s2 mounted
-bash-3.2# diskutil mount disk0s5
Quantity Decrease on disk0s5 mounted
-bash-3.2# diskutil listing disk0
/dev/disk0
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme +268.4 GB disk0
1: EFI EFI 209.7 MB disk0s1
2: Apple_HFS Higher 133.8 GB disk0s2
3: Apple_HFS Decrease 133.8 GB disk0s5
4: Apple_Boot Restoration HD 650.0 MB disk0s3
Stop the Terminal software.
Open Safari by choosing “Get Assist On-line”. Below Safari Preferences, set “File obtain location:” to the Decrease gadget, as proven beneath.
At this level, I provide two choices. The primary possibility can be to make use of web site (or https://maclinks.publicvm.com) to get the URL or hyperlink essential to obtain the InstallMacOSX.dmg file for Mountain Lion from Apple. Should you use the primary possibility, then you may skip the remainder of this step. The second possibility can be to proceed with the remainder of this step.
Subsequent, goto https://help.apple.com/kb/DL2076. If you’re utilizing a more recent model of Safari, then a Obtain button will seem, as proven beneath. If the button seems then choose the button, obtain the InstallMacOSX.dmg file to /Volumes/Decrease and proceed to the subsequent step. In any other case, full the remainder of this step.
Almost definitely, the Obtain button is not going to seem, as proven beneath.
From menu bar, choose File→Save As…, then set the format to Web page Supply, as proven beneath. When completed, choose the Save button, the give up Safari.
From the menu bar, choose Utilities→Terminal to open a Terminal window and enter the command beneath. This can output textual content containing the URL assigned to the lacking Obtain button.
grep updates /Volumes/Decrease/Mac OS X Mountain Lion Installer.html
Once I run the above command, the next was output.
"metaUrl": "
From which, the next URL might be extracted.
Out of your output, copy the Url, give up Terminal, open Safari and paste the URL as the placement to open. This could obtain the InstallMacOSX.dmg file to /Volumes/Decrease.