Difference between revisions of "Diskruimte"
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+ | = Diskruimte = | ||
De diskruimte op [[Hardware_servers|C&CZ servers]] kan door gebruikers benaderd worden vanaf allerlei [[Hardware_servers|C&CZ servers en werkplekken]], maar ook vanaf andere werkplekken of zelfs vanaf thuis met WinSCP of [[Vpn|VPN]]. | De diskruimte op [[Hardware_servers|C&CZ servers]] kan door gebruikers benaderd worden vanaf allerlei [[Hardware_servers|C&CZ servers en werkplekken]], maar ook vanaf andere werkplekken of zelfs vanaf thuis met WinSCP of [[Vpn|VPN]]. | ||
Van vrijwel alle schijven die onder beheer van C&CZ staan, worden regelmatig [[Backup|backups]] gemaakt, zodat bij kleine of grote calamiteiten de data niet verloren gaan. | Van vrijwel alle schijven die onder beheer van C&CZ staan, worden regelmatig [[Backup|backups]] gemaakt, zodat bij kleine of grote calamiteiten de data niet verloren gaan. | ||
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[en] | [en] | ||
+ | = Diskspace = | ||
The diskspace on [[Hardware_servers|C&CZ servers]] can be used from all kind of [[Hardware_servers|C&CZ servers and personal computers]], but also from other PCs or even from home with WinSCP or [[Vpn|VPN]]. Almost all disks that are managed by C&CZ, are being [[Backup|backupped]] regularly, in order to be able to restore data in case of small or large calamities. | The diskspace on [[Hardware_servers|C&CZ servers]] can be used from all kind of [[Hardware_servers|C&CZ servers and personal computers]], but also from other PCs or even from home with WinSCP or [[Vpn|VPN]]. Almost all disks that are managed by C&CZ, are being [[Backup|backupped]] regularly, in order to be able to restore data in case of small or large calamities. | ||
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Revision as of 23:02, 15 April 2021
Diskspace
The diskspace on C&CZ servers can be used from all kind of C&CZ servers and personal computers, but also from other PCs or even from home with WinSCP or VPN. Almost all disks that are managed by C&CZ, are being backupped regularly, in order to be able to restore data in case of small or large calamities.
Home directories
Every user with a Science login has or is entitled to an amount of disc space of a few Gigabytes on a server. This disc space is called the "home-directory" on Unix/Linux computers and the "H- or U-drive" on Windows-computers. The location of this homedirectory (which server) can be viewed on the Do-It-Yourself website.
Naming
Username | guest204 |
SMB (Windows/...) name | \\home1.science.ru.nl\guest204
or |
URL (Apple/Linux/Android/...) name | smb://home1.science.ru.nl/guest204
or |
NFS (C&CZ beheerd Linux) name | /home/guest204 |
Access rights
Long ago the (Unix) home directory of a user, except for a few protected areas, was readable for all users of the server. Today the home directory of a user can be accessed by the user himself. The user can change the access rights. C&CZ checks for home directories that are writable by other users.
Access through NFS
Mounting a home (U:) drive on Linux via NFS/Kerberos.
Diskspace for groups/institutions/projects: there are a few fileservers with RAID storage with partitions that can be rented for a period of 3 years. The price for new discs or a new 3 year extension of an older disc is per July 2018 for FNWI departments:
size | incl. backup | without backup |
ca. 200 GB | € 40 per year | € 10 per year |
ca. 400 GB | € 80 per year | € 20 per year |
Although even the cheapest version is much more expensive than buying 1 disk for 1 PC, it often makes sense, because of the reliability (redundant disks, backup, support contract) and security (stable server). One or more folders on such a partition can be mapped as a network drive on Windows PCs or NFS-mounted on Unix/Linux hosts. The ability to read and/or write files on these folders can be limited to a group of logins. That group can be managed by the department on the Do-It-Yourself website.
C&CZ has service contracts for these servers and has spares on site, so a failure can be resolved quite fast. Because the disks are part of a RAID set, the failure of 1 single disk or even 2 disks, will not give a disruption of service for users. The partitions are backed up (daily and incremental). Even in the case when the whole server room is lost, data can (eventually) be restored.
Ceph Storage
Starting November 2019 we can provide almost unlimited storage for the Faculty of Science using our Ceph storage cluster. The way Ceph works there is a tradeoff for performance and redundancy. Also it is possible to improve redundancy above single server RAID-6 level, with the additional redundancy options. NB Ceph volumes have no backups, the volumes tend to be too large to backup
Pool | why | price per TB per year without backup |
Erasure coding 8+3 | cheap | € 45 |
Erasure coding 5+7 | cheap + additional redundancy | € 80 |
3 copy | faster r+w | € 100 |
4 copy | faster r+w + additional redundancy | € 135 |
The Ceph storage can be used as windows share, nfs share or S3 object store. Object store is a different concept than a normal filesystem, so data stored in a windows or nfs share cannot be accessed using the s3 protocol.
The performance properties of Ceph are different from traditional single server storage; write speed usually exceeds read speed and lots of small files is killing for throughput, even worse than on traditional storage.
NB, 1 TB is 1.000.000.000.000 bytes
Naming
Volume name | sharename |
SMB (Windows/..) name | \\sharename-srv.science.ru.nl\sharename |
URL (Apple/Linux/Android/...) name | smb://sharename-srv.science.ru.nl/sharename |
NFS (C&CZ-beheerd Linux) name | /vol/sharename |
Access rights
Most of the shared disks can be read and written by a specific group of users. The owners of this group can administer on the Do-It-Yourself website which accounts are a member of this group.
Requests
A request for one or more network discs should contain:
- requested name of the disc(s)
- requested size (max ca. 500GB with backup)
- possibly requested backup schedules to lower the price (Daily/Monthly/Yearly)
- Science loginname of an owner
- possibly Science loginname of a member
- charge account (kostenplaats) or project code for the costs in the first three years.
Every now and then you want to send one or more large files (more than a few tens of MBs) to someone else within the Faculty, mail is unsuited for those large files. To make this easy, one can use a network share, where one can store large files temporarily in order to have someone else copy the files from this location. Note that this is explicitly meant for temporary storage, we do not make backups of this share, every day we remove files older than 21 days old. When copying files to this share, make sure the file timestamps are updated. Some copy programs (like rsync) maintain the original timestamps and older files will be deleted. To update timestamps, you can use the following command:
find . -exec touch {} +
This share can also be used to store temporary files only readable for yourself by using a different name for the share. Note that also in this case, old files will be removed.
Please create a subdirectory with your name first, and put your files in that directory.
For files totaling less than 250GB, also Surfdrive is an alternative. For sending files up to 500GB SURFfilesender can be used.
Naming
Volume name | temp |
SMB (Windows/..) name | \\temp-srv.science.ru.nl\share or |
URL (Apple/Linux/Android/...) name | smb://temp-srv.science.ru.nl/share or |
NFS (C&CZ-beheerd Linux) name | /vol/temp |
Access rights
- Readable by all users: share
- Only readable for the owner: onlyme