G06F16/181

WORM DATA FALSIFICATION DETECTION
20180165282 · 2018-06-14 ·

A computer determines the file system that contains a first partition, a second partition and a third partition. The first partition contains metadata comprising metadata associated with a WORM-specified file, and metadata associated with a rewritable file. The second partition contains a file body of a file and a copy of the metadata. The third partition contains metadata associated with the WORM-specified file. The computer receives a request to set a file setting of a target file to a WORM setting. The computer stores metadata associated with the target file in the first partition, the second partition, and the third partition.

Records declaration filesystem monitoring

Techniques for managing records on a filesystem to enforce a record disposition protocol. Embodiments identify records on the filesystem using one or more record definitions. Each record definition may contain a conditional statement which, if satisfied by a particular file on the filesystem, indicates the particular file as a record. Embodiments may then monitor file activity for each of the identified records and upon detecting the file activity, may enforce the record disposition protocol for the record. Such enforcement may include preventing the file activity, and may further include logging information related to the file activity.

WORM DATA FALSIFICATION DETECTION
20180075027 · 2018-03-15 ·

A computer determines the file system that contains a first partition, a second partition and a third partition. The first partition contains metadata comprising metadata associated with a WORM-specified file, and metadata associated with a rewritable file. The second partition contains a file body of a file and a copy of the metadata. The third partition contains metadata associated with the WORM-specified file. The computer receives a request to set a file setting of a target file to a WORM setting. The computer stores metadata associated with the target file in the first partition, the second partition, and the third partition.

Support for worm cartridges realized by linear tape file system (LTFS)

When a WORM cartridge is formatted for Tape File System (LTFS) in advance, such as prior to shipment, Linear Tape File System Library Edition (LTFS LE) is expanded by software to reduce consumption of the index partition and to support elimination of the appending of unnecessary data. More specifically, instead of recording metadata in the index partition during normal unmounting, the metadata is recorded in separate local storage such as on hard disk drive (HDD), and the index partition is updated only when the cartridge is ejected from the library. In this way, the present invention is able to significantly reduce the frequency of index partition updates. Because an update occurs only when the user intentionally ejects a cartridge, overflow of the index partition before overflow of the data partition can be prevented.

Support for WORM cartridges realized by linear tape file system (LTFS)

When a WORM cartridge is formatted for Tape File System (LTFS) in advance, such as prior to shipment, Linear Tape File System Library Edition (LTFS LE) is expanded by software to reduce consumption of the index partition and to support elimination of the appending of unnecessary data. More specifically, instead of recording metadata in the index partition during normal unmounting, the metadata is recorded in separate local storage such as on hard disk drive (HDD), and the index partition is updated only when the cartridge is ejected from the library. In this way, the present invention is able to significantly reduce the frequency of index partition updates. Because an update occurs only when the user intentionally ejects a cartridge, overflow of the index partition before overflow of the data partition can be prevented.

WOM code emulation of EEPROM-type devices

A system for write-once memory (WOM) code emulation of EEPROM-type devices includes, for example, a host processor for sending data words for storing in a WOM (Write-Only Memory) device. A host interface receives the data words for encoding by a WOM controller. An emulator programs the WOM-encoded data and an address identifier as an entry of the WOM device. The emulator overwrites previously programmed WOM-encoded data by searching entries of a current active page of a WOM device to locate a programmed WOM entry that includes the searched-for address identifier and the previously written WOM-encoded data word. When the previously written WOM-encoded word cannot be correctly overwritten, the contents of the second WOM-encoded word are stored in a new entry. When the current active page is substantially full, the new entry is stored a new page and the current active page is block-erased.

Storage system and method for processing data operation request
09753941 · 2017-09-05 · ·

A storage system and a method for processing a data operation request are disclosed. The method is applied to a storage system that has a write once read many (WORM) function. In the method, after the storage system receives a data operation request, which is used to change data stored in the storage system, sent by an application server, the storage system acquires a time difference between a real-time clock (RTC) and a reference clock, wherein the RTC is configured to provide system time for the storage system, and the reference clock cannot be modified when the system is running. Then, the storage system determines whether the time difference is greater than an accumulated time precision error of the reference clock, and refuses to execute the data operation request when the time difference is greater than the accumulated time precision error.

Write Once Read Many Media Methods and Systems
20170228394 · 2017-08-10 ·

A method and/or system for providing for write once read many (WORM) times from at least some addresses of a storage drive that is otherwise manufactured for multiple writes to individual addresses. In at least one embodiment, a WORM area(s) is defined by a START_LBA and an END_LBA and the method uses a HWM_LBA to determine whether a LBA in the WORM area has been written to previously and to prevent previously written to LBA(s) in the WORM area from being rewritten. In at least one embodiment where there are multiple WORM areas, each WORM area has its own respective START_LBA, END_LBA and HWM_LBA.

Method for improving mean time to data loss (MTDL) in a fixed content distributed data storage
09672372 · 2017-06-06 · ·

An archival storage cluster of preferably symmetric nodes includes a data protection management system that periodically organizes the then-available nodes into one or more protection sets, with each set comprising a set of n nodes, where n refers to a configurable data protection level (DPL). At the time of its creation, a given protection set is closed in the sense that each then available node is a member of one, and only one, protection set. When an object is to be stored within the archive, the data protection management system stores the object in a given node of a given protection set and then constrains the distribution of copies of that object to other nodes within the given protection set. As a consequence, all DPL copies of an object are all stored within the same protection set, and only that protection set. This scheme significantly improves MTDL for the cluster as a whole, as the data can only be lost if multiple failures occur within nodes of a given protection set. This is far more unlikely than failures occurring across any random distribution of nodes within the cluster.

File system implementing write once read many (WORM)

The embodiments deal with files that are already present in a storage when mounting the storage in a file system and files created after the mounting as different groups. (Metadata of) the files is classified. The files are each divided into metadata (index) and a file main body and are recorded on different storage areas, that is, an index partition (IP) and a data partition (DP), associated with each other. This file system is effective in a storage format in which a new file is merely written and an already written file is not updated or deleted (for example, a tape medium used in the LTFS). The embodiments implement a WORM file system by rejecting a request to update or delete a file that is present at mounting as a WORM file and permitting update or deletion of a file that is created after mounting until the storage is unmounted.