Re: Trouble recovering ext3 partition 2 Post by Fiona » Tue Jul 08, am TestDisk doesn't let you recover a partition which ends after disk limit. In some cases I've had a trick to increase the amount of cylinder using the menu geometry to make your partition accessible and at least to have a try to list your data. I'm missing info about your disk, your current partition structure and the results of "Deeper Search".
Looks like the attachment didn't come through. What does it mean for a partition to end after the disk limit? How do I figure out the correct number of cylinders to set? Re: Trouble recovering ext3 partition 4 Post by remy » Tue Jul 08, pm you probably found the good partition, but on the wrong beginning position because testdisk detected a superblock.
Try to change options to match "cylinder boudary : no", and run again the deepersearch. If it's not enough, try to select 'none' instead of 'intel' partition type. Typically, we will traverse 3 blocks to read or write a directory entry, and that number increases to with really huge directories.
But this is really nothing compared to normal Ext2, which traverses several hundred blocks in the same situation. Most of the file also directory, symlink, device Some other attributes are only available as extended attributes. Under most implementations, the owner and group are 16bit values, but on some recent Linux and Hurd implementations the owner and group id are 32bit.
Extended attributes are name:value pairs associated permanently with files and directories, similar to the environment strings associated with a process. An attribute may be defined or undefined. If it is defined, its value may be empty or non-empty. Extended attributes are extensions to the normal attributes which are associated with all inodes in the system. They are often used to provide additional functionality to a filesystem - for example, additional security features such as Access Control Lists ACLs may be implemented using extended attributes.
Extended attributes are accessed as atomic objects. Reading retrieves the whole value of an attribute and stores it in a buffer. Writing replaces any previous value with the new value. Extended attributes are stored on disk blocks allocated outside of any inode. Inodes which have all identical extended attributes may share the same extended attribute block. The attribute values are on the same block as their attribute entry descriptions, aligned to the end of the attribute block.
This allows for additional attributes to be added more easily. The size of entry headers varies with the length of the attribute name. The block header is followed by multiple entry descriptors.
The entry descriptors are sorted by attribute name, so that two extended attribute blocks can be compared efficiently. Attribute values are aligned to the end of the block, stored in no specific order.
No additional gaps are left between them. This value is incremented everytime a link is created to this attribute block and decremented when a link is destroyed. Whenever this value reaches 0 the attribute block can be freed. This effectively restrict the amount of extended attributes to what can be fit in a single block. Procedure 5. Procedure to compute Extended Attribute Header Hash.
Do a cyclic bit shift of 16 bits to the left of the 32bits hash value, effectively swapping the upper and lower 16bits of the hash. Perform a bitwise OR between the extended attribute entry hash and the header hash being computed.
The following bits are currently defined:. Enabling this bit will cause random data to be written over the file's content several times before the blocks are unlinked. Make sure to study the implementation notes before relying on this option. When supported by the implementation, setting this bit will cause the deleted data to be moved to a temporary location, where the user can restore the original file without any risk of data lost.
This is most useful when using ext2 on a desktop or workstation. The file's content is compressed. The file's content in memory will be constantly synchronized with the content on disk.
This is mostly used for very sensitive boot files or encryption keys that you do not want to lose in case of a crash. The blocks associated with the file will not be exchanged. If for any reason a file system defragmentation is launched, such files will not be moved.
Mostly used for stage2 and stage1. Writing can only be used to append content at the end of the file and not modify the current content. Example of such use could be mailboxes, where anybody could send a message to a user but not modify any already present. Setting this bit will protect the file from deletion. The only good use I can think of that are related to security. This flag is set if one or more blocks are compressed. When this flag is set, the file system implementation will not uncompress the data before fowarding it to the application but will rather give it as is.
When this bit is set, the format of the directory file is hash indexed. I would like to personally thank everybody who contributed to this document, you are numerous and in many cases I haven't kept track of all of you. Be sure that if you are not in this list, it's a mistake and do not hesitate to contact me, it will be a pleasure to add your name to the list. The Second Extended File System. Table of Contents About this book 1. Historical Background 2.
List of Figures 4. Performance of Indexed Directories 5. List of Tables 2. Impact of Block Sizes 3. Sample 20mb Partition Layout 3. Superblock Structure 3. Block Group Descriptor Structure 3. Inode Structure 3. Defined Reserved Inodes 3. Sample Inode Computations 4.
Linked Directory Entry Structure 4. Defined Inode File Type Values 4. Indexed Directory Root Structure 4. Defined Indexed Directory Hash Versions 4. Extended Attribute Block Layout 5. Behaviour Control Flags. About this book. Chapter 1. Historical Background. Chapter 2. Table 2. Block Groups. This definition comes from the Linux Kernel Documentation with some minor alterations. Symbolic Links. This definition comes from Wikipedia.
Chapter 3. Disk Organization. Table 3. Sample Floppy Disk Layout, 1KiB blocks Block Offset Length Description byte 0 bytes boot record if present byte bytes additional boot record data if present -- block group 0, blocks 1 to -- byte bytes superblock block 2 1 block block group descriptor table block 3 1 block block bitmap block 4 1 block inode bitmap block 5 23 blocks inode table block 28 blocks data blocks.
Sample 20mb Partition Layout Block Offset Length Description byte 0 bytes boot record if present byte bytes additional boot record data if present -- block group 0, blocks 1 to -- byte bytes superblock block 2 1 block block group descriptor table block 3 1 block block bitmap block 4 1 block inode bitmap block 5 blocks inode table block blocks data blocks -- block group 1, blocks to -- block 1 block superblock backup block 1 block block group descriptor table backup block 1 block block bitmap block 1 block inode bitmap block blocks inode table block blocks data blocks -- block group 2, blocks to -- block 1 block block bitmap block 1 block inode bitmap block blocks inode table block blocks data blocks.
Note In Linux, at least up to 2. Note As of Linux 2. Note Compression is supported in Linux 2. Block Group Descriptor Table. Block Bitmap. Inode Bitmap. Inode Table. Note Linux sets this value to 0 if the file is not a regular file i. Note Always 0 in Linux since fragments are not supported. Locating an Inode. Category : Data Recovery. Cookies help us deliver our services.
Some cookies serve for direct advertising data collection for ads personalisation. By using our services, you agree to our use of cookies. More information OK. Even armed with an even more detailed partition list didn't make a difference.
It could not read any files from the partitions listed. That's where I'm at now. I have no other avenues to take that I can find. I know a raid is not a backup, as is plain now, but I didn't think I could afford a backup solution that could encompass a Tera-byte or two. That's what I'll be looking into the next few days. In the meantime I hope you guys forgive the skyscraper of text and can help me find a solution. Ohh one more thing The configuration of that last partition list in testdisk seems awfully suspicious to me.
It's a set of five possible partitions early on followed by another set of five possible partitions. Matching the number of devices in the array. Perhaps it's a clue. You might want to take a look at ddrescue now to see if anything at all can be recovered I'm thinking you jumped the gun and resized the fs before it was finished.
From the dmesg output you can see that it had to finish the reshape after you rebooted:. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams?
Learn more. Ext4 superblock corrupted after successful? Asked 10 years, 8 months ago. Active 10 years, 8 months ago.
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