1KAFS(7) In-kernel AFS filesystem KAFS(7)
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6 kafs - In-kernel AFS filesystem
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9 kafs is a network filesystem driver in the Linux kernel that is able to
10 access AFS cells and the servers contained therein to locate the logi‐
11 cal volumes that comprise the cell and the files contained in each vol‐
12 ume.
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14 It supports transport over IPv4 UDP and IPv6 UDP and security based on
15 Kerberos. The authentication token is used to define the user for the
16 purpose of providing access control as well as providing communications
17 security.
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19 The filesystem is of type "afs" and the mount command can be used to
20 mount afs volumes manually using the "-t" flag on mount(8).
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24 The kafs-client package should be installed to so that systemd is con‐
25 figured to include a mount of AFS dynamic root on /afs. Note that
26 mounting /afs is not enabled by default, so if it is needed, then sys‐
27 temd should be told to enable it. This can be done with the following
28 step:
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30 systemctl enable afs.mount
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32 This will mount a special directory on /afs which will be populated by
33 an automount directory for each cell listed in the configuration.
34 Doing a pathwalk into one of these directories will result in the
35 afs.cell volume from the cell being mounted onto that directory.
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37 Local configuration should be placed in a file in the
38 /etc/kafs/client.d/ directory. This will be included from client.conf
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41 Typically in the local configuration, the local cell name would be
42 specified and backup details of its Volume Location server addresses
43 would be given.
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45 Also any overrides for the @sys filename substitution would be speci‐
46 fied. See kafs-client.conf(5).
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50 Once the kafs-client is set up (and if there's no local cell, this is
51 practically zero-conf, provided the cells to be accessed are properly
52 set up with AFSDB or SRV records in the DNS), the /afs directory can be
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55 ls /afs/<cell>/location/within/cell
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57 For example:
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59 ls /afs/rivendell.example.com/doc
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61 The user isn't limited to cells listed in /afs, but any cell can be
62 tried by just substituting the name of the cell into the above formula.
63 It does require the target to have DNS-based configuration provided.
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65 Note that each logical volume gets a discrete superblock and links
66 between volumes turn into kernel mountpoints that, if stepped on, cause
67 the appropriate volume to be mounted over them.
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71 kafs supports Kerberos-based authentication and communication encryp‐
72 tion through the use of Kerberos. The kinit program can be use to
73 authenticate with a Kerberos server:
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75 kinit myname@RIVENDELL.EXAMPLE.COM
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77 and then the aklog-kafs program to get a ticket for the kernel filesys‐
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80 aklog-kafs rivendell.example.com
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82 This will be placed on the caller's session keyring and can be viewed
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85 keyctl show
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87 Note that the default realm is assumed to be the same as the cell name,
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95 aklog-kafs(1), kafs-client.conf(5), keyctl(1), kinit(1), rxrpc(7),
96 session-keyring(7), systemctl(1)
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100Linux 16 Apr 2019 KAFS(7)