infra: add new udev rules

userspace/udev/65-mars.rules

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+# This file contains the rules to create named MARS devices.
+
+# Although I want to clear the sticky bit explicitly via MODE=, it
+# does not work. This seems to be an undocumented feature; I found
+# only an changelog entry dealing with the sticky bit, which I did
+# not understand. Probably the RUN= can be made simpler.
+
+# The following description is stolen from the DRBD udev rules.
+# The rule itself is very different, not stolen.
+# DO NOT WRAP THIS LINE
+#
+# old udev does not understand some of it,
+# and would end up skipping only some lines, not the full rule.
+# which can cause all sort of trouble with strange-named device nodes
+# for completely unrelated devices,
+# resulting in unusable network lookback, etc.
+#
+# in case this is "accidentally" installed on a system with old udev,
+# having it as one single line avoids those problems.
+#
+# DO NOT WRAP THIS LINE
+SUBSYSTEM=="block", KERNEL=="mars/*", MODE="00600", GROUP="disk", RUN="/bin/chmod -t /dev/$kernel"

userspace/udev/README

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+TST August 2014
+
+On some distros / versions, udev rules for MARS are needed.
+
+Without any udev rules, /dev/mars/mydata is created with the sticky bit set.
+As a result, the device will not vanish when leaving primary state.
+
+In turn, some commands like "marsadm secondary" will complain about that
+by means of timeouts.
+
+On other distros / versions, catch-all rules are present which _would_
+prevent the sticky bit problem. However, some syntax errors prevent this.
+
+This directory contains distro- and version-dependent stuff. I did not have
+the time to fully analyze all distros / distro versions and their udev
+rules.
+
+Since I am not an expert in writing udev rules (and I just needed
+a quickfix for my own work), the files in this directoy should
+be regarded as examples.
+
+For example, the file 65-mars.rules should be copied to /lib/udev/rules.d/
+on some newer Debian distros. OTOH, some elder Debians don't seem to
+need this (but may need debian-udev.patch).
+
+Distro maintainers should improve on this and/or provide better solutions.