Unc file system

What is the UNC path? Category: technology and computing shareware and freeware. Universal Naming Convention A standard for identifying servers, printers and other resources in a network, which originated in the Unix community.

What is a directory path? How do I copy a full file path? What is a relative path? What is the absolute path? What does UNC stand for? Universal Naming Convention. Does path include filename? How do I find a file path? In the File Explorer, select View in the toolbar. What is Posix path? What is a hardened UNC path? What is an example of a file path? How do I find the path of a shared folder?

Open the shared drive in File Explorer. What port does UNC use? What is a network share path? How do I map a network drive? Map a network drive. How do I map a drive in Windows 10? Just follow these steps:. GetFullPath String, String with relative directory segments; it is never possible to navigate past the volume. DOS device paths are fully qualified by definition.

Relative directory segments. Current directories never enter into their usage. The following example illustrates some of the ways in which you can refer to a file when using the APIs in the System. IO namespace. The example instantiates a FileInfo object and uses its Name and Length properties to display the filename and the length of the file.

Almost all paths passed to Windows APIs are normalized. During normalization, Windows performs the following steps:. This normalization happens implicitly, but you can do it explicitly by calling the Path.

The first step in path normalization is identifying the type of path. Paths fall into one of a few categories:. The type of the path determines whether or not a current directory is applied in some way. It also determines what the "root" of the path is. A path that begins with a legacy device name is always interpreted as a legacy device by the Path.

GetFullPath String method. If a path isn't fully qualified, Windows applies the current directory to it. UNCs and device paths do not have the current directory applied. If the path starts with a single component separator, the drive from the current directory is applied. If the path starts with a drive letter, volume separator, and no component separator, the last current directory set from the command shell for the specified drive is applied.

If the last current directory was not set, the drive alone is applied. These "drive relative" paths are a common source of program and script logic errors. Assuming that a path beginning with a letter and a colon isn't relative is obviously not correct.

If the path starts with something other than a separator, the current drive and current directory are applied. Relative paths are dangerous in multithreaded applications that is, most applications because the current directory is a per-process setting. Any thread can change the current directory at any time.

Starting with. NET Core 2. GetFullPath String, String method to get an absolute path from a relative path and the base path the current directory that you want to resolve it against. If they are present, a series of slashes that follow the first two slashes are collapsed into a single slash. As the path is processed, any components or segments that are composed of a single or a double period. For a double period, the current segment and the parent segment are removed, since the double period refers to the parent directory.

Parent directories are only removed if they aren't past the root of the path. The root of the path depends on the type of path. Along with the runs of separators and relative segments removed earlier, some additional characters are removed during normalization:. If a segment ends in a single period, that period is removed. Backup volumes exist for other AFS volumes that receive daily backups.

If you are working in project space, for example, you may be able to get an instant restoration there as well:. Make sure you are authenticated to AFS i. Cd into the directory from which you lost the file. If you get an error from your command you probably do not have permissions to the volume.

Email help cs. If the command succeeds, cd into the name given as the mount point, and copy the file back into project space. T hen cd out of the backup volume and type. You only have until the next AFS backup runs to do this restoration. After that, the backup will not have the old file. If you encounter any problems, send mail to help cs-old. See the disk usage help page on how to determine how much space you are using and controlling your disk usage.

Computer Services monitors disk usage, so this rarely occurs. Your home directory volume is in a physical partition with other volumes. Please email help cs-old. You can delete any file you have created that day. That space will be reclaimed and be immediately available. Deleting older files will reclaim space after the next backup runs. For an explanation of why this is, please see How AFS backup volumes work below. Volumes whose names end in.

The AFS backup process locks the volume while the backup is run, so to minimize the loss of access, these backup volumes are created early in the morning and the backup software backs them up instead of the original volume. Backup volumes are identical to the original volume when they are created. Over the course of the day, they get further away from the original, as the owner modifies files.

When created, they actually occupy very little space, just the amount needed to point to the same data blocks that the original does. The modified blocks are written to a different location. If the file is outside of AFS, the old block is then freed for reuse.

So as files change, the backup volume gradually occupies more space in the partition. The next night, the two are synchronized and those blocks are reclaimed.

From this discussion, you can see that the way you use your disk space will affect how much space you have through the day. If, as a matter of course, you throw away a MB directory and copy it over from elsewhere every day, you are effectively occupying MB within that space, for the old one pointed to by the backup volume , and MB for the new copy.

This type of usage can cause significant inconvenience to the others who share your AFS partition. With AFS, it is not obvious which file server actually holds your volume. There is a 24 hour online snapshot of all files in AFS playpen space; if you delete files and they were there during the last online backup you can restore the files as described below. The afs snapshot takes place at 2am and usually finishes by am.

To use the AFS playpen space, you first need to email help cs-old. If you need more you can request an additional 8GB added to your quota. There are currently GB available in playpen space, and a lot of folks use this space.

If you want to make space that is accessible under your home web page:. If your files were present at that time, they will be available as read only files until the next 2am snapshot is taken.

Remember, a snapshot is taken every night and your files will be lost if you do not get them back before the next snapshot.

For instance, say you create a file Monday morning and work on it all day. Tuesday at am a backup volume is created that contains all the data at the time of the backup. You then accidently delete the file Tuesday at pm. This page gives information on AFS tokens, access control lists ACLs , protection groups, and home directory permissions.

Tokens contain a time stamp and are valid for a pre-set amount of time. The default lifetime of a token at UNC is one week. You can use the AFS command aklog to extend the life of a token or to get a new token if your original token expires. Tokens are the mechanism of authentication. Tokens provide security because in order for an application to ask for the token, it must know an encryption key, and in order to understand that a token has been granted, it must also have an encryption key.

This makes it very difficult for someone outside the application to intercept the password, or to even ask for a token. If the cache manager holds a token for you, you are considered authenticated to AFS. You get a token by logging in. We have set up the login process to authenticate your password within AFS. To see that this has happened, you can type the tokens command:. This output says that the cache manager holds for you a token for the cell cs-old. You may hold additional tokens for different cells, but you may not have more than one token for a particular cell.

Tokens are specific to a machine, so authenticating on one machine does not give you a token for another workstation. Tokens expire after some period of time and need to be renewed. Also, tokens do not automatically go away when you log out, so that when you run programs overnight the background programs can use the tokens to access files.

You can remove a token by using the unlog command:. An access control list ACL is a list of permissions attached to an object.

An ACL specifies which users or system processes are granted access to objects, as well as what operations are allowed on given objects. As a result, when you move files between directories, you may have changed the permissions.

When you create a new subdirectory, it automatically inherits the ACL that the parent had at the time it was created. The file bits may be used to further restrict access to a file that the ACL allows access to. Remember, however, that the user bits are applied to anyone who has access to the file; the owner of the file is irrelevant.

Also, anyone who has write access to the file through the ACL will be allowed to change the protection bits on the file using chmod. AFS acls can be complicated. This is especially true of directories where you plan to house sensitive information. For example, if you have files in your www. If your AFS ACLs are not configured properly, search engines like Google can find your pages, catalog them, and keep cached copies of them. For example:. The system:anyuser is any user with access to the AFS system, whether or not he has been authenticated to your AFS cell.