MacOS partition doesnt boot up and shows as FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF

Quick specs: Macbook Pro Mid2012 500GB SSD thats been in the Macbook for around 4 years MacOS Mojave BOOTCAMP Windows (100GB)

Yesterday while I was browsing on Safari i refreshed a site and my Macbook Pro just hanged and the spinning cursor appeared when hovering over Safari, everything else seemed to be working, so i tried closing Safari via the dock (the icons still enlarged when i moved over then) but as soon as i right clicked on Safari the dock froze as well. So i gave it a few minutes to see if its going to unfreeze but it didnt. So naturally i restarted the machine only for it to show the circle with line across instead of the apple logo. I restarted it and held ALT. A “Mac” came up but not the “Windows” clickable thingy. I selected the Mac and again the same story with the line across the circle. Restarted the Mac again now holding Command-R for internet recovery. Opened Disk Utility and i could see this enter image description here Then i verified the “525.11 GB Crucial…” and i got this: enter image description here

Then i clicked repair volume and it said it was fixed so i restarted the Macbook but i still got the same cross thing and when i got back to Disk Utility and verified the volume again, it again gave me the same error. (forgot to add, tried to reinstall OSX but only the Windows partition showed up)

Fast forward to today I tried to do what i saw in this Stack Exchange. I removed the Windows partition and then removed the Mac one, then i tried to remount the OSX partition but i got no space available error enter image description here Now instead of showing disk0s2 and BOOTCAMP under the Crucial volume, it only shows the BOOTCAMP one. enter image description here


Heres the list before i tried to unmount: enter image description here

And after: enter image description here

Heres a few more pictures i took:

Heres me retrying to repair disk volume after the Macbook was turned off for a day (but before i unmounted it!!!). I tried to repair it a few times but getting th same error and then after like 3-5 times it just said it repaired. Verify still says theres an error but when i click repair it says its repaired enter image description here

Heres a repair volume in terminal, it gives me an error of unrecognized file system (also before i unmounted stuff)

-bash-3.2# diskutil repairVolume /dev/disk0s2 Error starting file system repair for disk0s2: Unrecognized file system (-69846) 

Heres the CoreStorage and a command i saw someone request it in some other Stack Exchange

-bash-3.2# diskutil cs list No Corestorage logical volume groups found -bash-3.2# gpt -r show /dev/disk0s2      start          size      index      contents          0     829890520 

Internal hard disk does not mount on Ubuntu: Just one unknown partition

I have received an old hard drive (previously used in Drobo) and want to extract its data. Not sure how was used in Drobo and what has been the filesystem type.

I connect it to my systems which has Ubuntu 18.04 installed. The disk is recognized in the “Disks” but cannot be mounted. The drive seems to have only one partition (e.g. /dev/sdc) and shown as Unknown.

Image taken from Disk

When checking the options in the gears on the bottom-left side (see attached), all the options except “Format Partition, Create Partition Image, Restore Partition Image, and Benchmark Partition” are deactivated.

I was wondering if there is a solution for how to extract the data from this hard drive?

Thanks in advance for your comments. Cheers

SSHFS mount remote partition of Raspberry Pi

I am trying to mount the two partitions of my Raspberry Pi using sshfs. I am aware that I could just take out the SD card and use the regular mount, but I wanted to see if this was possible (I don’t see any reason why it wouldn’t).

So I have my Pi at pi@xxx.xxx.xxx.xxand two local folders at mnt/fat32 and mnt/ext4 (Note: NOT /mnt/...). Running lsblk on the pi tells me that the partitions’ names are mmcblk0p1 and mmcblk0p2` (see below [1]).

Locally, I tried running sudo sshfs -o allow_other,default_permissions pi@xxx.xxx.xxx.xx:/dev/mmcblk0p1 mnt/fat32. However, I only get the following result: pi@xxx.xxx.xxx.xx:/dev/mmcblk0p1: Not a directory

What am I doing wrong? Looking this up online, I only found out that this should work.

[1]:

mmcblk0     179:0    0 14.5G  0 disk  ├─mmcblk0p1 179:1    0 42.9M  0 part /boot └─mmcblk0p2 179:2    0 14.4G  0 part / 

Can’t resize partition

My Disk Utility is showing me some Weird Stuff.

My current startup partition is showing as 155 GB, with (I was shocked to discover) 344 GB of unpartitioned free space:

enter image description here

I can try to resize the first partition by removing the “Free space” section, then hit “Apply”, but then I get this error:

enter image description here

Actually, if I try this a few times, I get variously different errors. Sometimes it even says it succeeds, but the partition size doesn’t seem to have changed.

When I retry this same sequence after booting from my recovery partition, basically the same result happens, except that now I have two “Free space” partitions, both showing 344 GB, in addition to the 155 GB startup partition.

What’s going on here, and how can I take advantage of my full 500 GB disk? Or do I not actually have a 500 GB disk??

Here’s the Disk Utility info for the physical disk – notice that it says it’s 500 GB, but the 155 GB partition takes up the whole blue bar:

enter image description here

I’m using High Sierra 10.13.6, on a Late 2011 MacBook Pro 13″.

Wiped System Partition… No OS.. How can I recover it back?

I successfully installed TWRP yesterday on my phone and then wanted to root it, but before doing that, I wanted to do a Full-Wipe of my phone, just leaving the phone with the OS, but for some reason, I left the System Partition Wipe option enabled and Wiped it. Now, I’m stuck in a bootloop without an OS, and I can only access TWRP and Download Mode.

How can I recover the system/install the OS again?

Phone Specs:

SAMSUNG J7 PRO (SM-J730GM),

Previous O.S: Nougat 7.0

Region: México TCE

Macintosh HD partition missing from startup options

I tried to shrink my Windows Bootcamp partition using third-party software which led to my Macintosh HD partition missing from startup options. Unfortunately I don’t have a recent backup for the whole drive to restore from. If I try to reinstall macOS from scratch it doesn’t see the partition either.

enter image description here

Disk utility sees it but it’s greyed out and is being shown as Unmounted without the option to mount it back.

enter image description here

Is there a way to fix this without wiping out the whole drive and reinstalling everything from scratch?

External FileVault-encrypted backup – corrupted partition map

My FV-encrypted external drive was working fine, and now it’s not.

In Disk Utility (GUI), it shows as “Unformatted”.

diskutil list:

    /dev/disk2 (external, physical):        #:                       TYPE NAME                    SIZE       IDENTIFIER        0:      GUID_partition_scheme                        *2.0 TB     disk2        1:                        EFI EFI                     209.7 MB   disk2s1        2:          Apple_CoreStorage iMax Backup 2018-12-22  2.0 TB     disk2s2        3:                 Apple_Boot Recovery HD             650.0 MB   disk2s3 

Obviously it’s “iMax Backup 2018-12-22” I want back.

sudo gpt -r show /dev/disk2:

       start        size  index  contents            0           1         PMBR            1           1         Pri GPT header            2          32         Pri GPT table           34           6                    40      409600      1  GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B       409640  3905087808      2  GPT part - 53746F72-6167-11AA-AA11-00306543ECAC   3905497448     1269536      3  GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC   3906766984      262150            3907029134          32         Sec GPT table   3907029166           1         Sec GPT header 

First Aid in Disk Utility:

Running First Aid on “Seagate BUP Slim RD Media” (disk2)  Checking prerequisites Checking the partition list Checking the partition map size Checking for an EFI system partition Checking the EFI system partition’s size Checking the EFI system partition’s file system Checking the EFI system partition’s folder content Checking all HFS data partition loader spaces Checking booter partitions Checking booter partition disk2s3 Verifying file system. Volume is already unmounted. Performing fsck_hfs -fn -x /dev/rdisk2s3 Checking Journaled HFS Plus volume. Checking extents overflow file. Checking catalog file. Checking multi-linked files. Checking catalog hierarchy. Checking extended attributes file. Checking volume bitmap. Checking volume information. The volume Recovery HD appears to be OK. File system check exit code is 0. Restoring the original state found as unmounted. Checking Core Storage Physical Volume partitions Verifying storage system Performing fsck_cs -n -x --lv --uuid E994BCCD-8FF0-44D2-AE64-8D3CA172EAA5 Checking volume disk2s2: Scan for Volume Headers disk2s2: Scan for Disk Labels Logical Volume Group E994BCCD-8FF0-44D2-AE64-8D3CA172EAA5 on 1 device disk2s2: Scan for Metadata Volume Logical Volume Group has a 24 MB Metadata Volume with double redundancy Start scanning metadata for a valid checkpoint Load and verify Segment Headers Load and verify Checkpoint Payload Load and verify Transaction Segment Incorporate 0 newer non-checkpoint transactions Load and verify Virtual Address Table Load and verify Segment Usage Table Load and verify Metadata Superblock Load and verify Logical Volumes B-Trees Unable to bootstrap transaction group 236233: cksum mismatch Continue scanning metadata for an older checkpoint Load and verify Segment Headers Load and verify Checkpoint Payload Load and verify Transaction Segment Incorporate 0 newer non-checkpoint transactions Load and verify Virtual Address Table Load and verify Segment Usage Table Load and verify Metadata Superblock Load and verify Logical Volumes B-Trees Unable to bootstrap transaction group 236232: cksum mismatch Continue scanning metadata for an older checkpoint Load and verify Segment Headers Load and verify Checkpoint Payload Load and verify Transaction Segment Incorporate 0 newer non-checkpoint transactions Load and verify Virtual Address Table Load and verify Segment Usage Table Load and verify Metadata Superblock Load and verify Logical Volumes B-Trees Unable to bootstrap transaction group 236231: cksum mismatch Continue scanning metadata for an older checkpoint Load and verify Segment Headers Load and verify Checkpoint Payload Load and verify Transaction Segment Load and verify Transaction Segment Load and verify Transaction Segment Incorporate 2 newer non-checkpoint transactions Load and verify Virtual Address Table Load and verify Segment Usage Table Load and verify Metadata Superblock Load and verify Logical Volumes B-Trees Unable to bootstrap transaction group 236228: cksum mismatch No valid commit checkpoint found The volume E994BCCD-8FF0-44D2-AE64-8D3CA172EAA5 was found corrupt and needs to be repaired Storage system check exit code is 1. Problems were found with the partition map which might prevent booting  Operation successful. 

which reports:

First Aid found corruption that needs to be repaired. To repair the startup volume, run First Aid from Recovery. Click Done to continue. 

(I tried it in Recovery mode. It said the same thing.)

TechTool Pro said it might have to reformat the disk to fix the partition map. DiskWarrior will only upgrade my ancient version by snail mail.

Unfortunately I have no idea what the GPT or First Aid stuff means. Can anybody who does tell me if there any hope of getting back my FV volume, and if so, how? (I don’t have the original. Today was the day I was going to restore files from the backup.)

Thank you.

2019 iMac, Mojave 10.14.5.

Convex hull partition of a set of points

Given a set $ S$ of $ n$ points in $ \mathbb R^2$ , denote by $ \mathrm{conv}(S)$ the convex hull of $ S$ . Let \begin{align*} S_1 &= \mathrm{conv}(S)\ S_{i+1} &= \mathrm{conv}\left(S \setminus \bigcup_{j=1}^i S_j\right). \end{align*}

Now $ S_1,\ldots$ forms a partition of $ S$ . Is there an $ O(n\log n)$ time algorithm for computing this partition?