X-Git-Url: http://git.ipfire.org/?a=blobdiff_plain;f=man%2Fcrypttab.xml;h=ee54499bfe7a13c86869b3c7c4e355a0e7d511a5;hb=3177b9270c88ba8b758d5ea9c8210248ea03b259;hp=2046911c7849517771c627b6ec39c08ee58d4420;hpb=5a36324962ba0ec5de4100945bc6d6bce494e956;p=thirdparty%2Fsystemd.git diff --git a/man/crypttab.xml b/man/crypttab.xml index 2046911c784..ee54499bfe7 100644 --- a/man/crypttab.xml +++ b/man/crypttab.xml @@ -60,13 +60,15 @@ device or file, or a specification of a block device via UUID= followed by the UUID. - The third field specifies an absolute path to a file to read the encryption key from. If the field - is not present or set to none or -, a key file named after the - volume to unlock (i.e. the first column of the line), suffixed with .key is - automatically loaded from the /etc/cryptsetup-keys.d/ and - /run/cryptsetup-keys.d/ directories, if present. Otherwise, the password has to be - manually entered during system boot. For swap encryption, /dev/urandom may be used - as key file. + The third field specifies an absolute path to a file to read the encryption key from. Optionally, + the path may be followed by : and an fstab device specification (e.g. starting with + LABEL= or similar); in which case, the path is relative to the device file system + root. If the field is not present or set to none or -, a key file + named after the volume to unlock (i.e. the first column of the line), suffixed with + .key is automatically loaded from the /etc/cryptsetup-keys.d/ + and /run/cryptsetup-keys.d/ directories, if present. Otherwise, the password has to + be manually entered during system boot. For swap encryption, /dev/urandom may be + used as key file. The fourth field, if present, is a comma-delimited list of options. The following options are recognized: @@ -253,6 +255,7 @@ Perform encryption using the same cpu that IO was submitted on. The default is to use an unbound workqueue so that encryption work is automatically balanced between available CPUs. + This requires kernel 4.0 or newer. @@ -261,9 +264,10 @@ Disable offloading writes to a separate thread after encryption. There are some - situations where offloading write bios from the encryption threads to a single thread degrades - performance significantly. The default is to offload write bios to the same thread because it benefits - CFQ to have writes submitted using the same context. + situations where offloading write requests from the encryption threads to a dedicated thread degrades + performance significantly. The default is to offload write requests to a dedicated thread because it + benefits the CFQ scheduler to have writes submitted using the same context. + This requires kernel 4.0 or newer. @@ -510,7 +514,8 @@ external /dev/sda3 keyfile:LABEL=keydev keyfile-timeout=10sThe PKCS#11 logic allows hooking up any compatible security token that is capable of storing RSA decryption keys. Here's an example how to set up a Yubikey security token for this purpose, using - ykman from the yubikey-manager project: + ykmap1 + from the yubikey-manager project: