* Makefile changes to build and install nossl versions of capture and
  console on a rack control node (or more generally, a physical node
  hosting boss/ops VMs that are not built on our XEN49 image).

* Add -I (insecure) option to capture, that listens on localhost only.

* Add systemd startup files for capture on ops and boss, I tested these
  on Ubuntu18.

Basic instructions:

* Clone the emulab-devel repo to the control node.

  git clone https://gitlab.flux.utah.edu/emulab/emulab-devel.git

* On the control node, install the libssl devel code:

  sudo apt-get update
  sudo apt-get install libssl-dev

* configure and build capture. Note that the obj-clientside directory might
  already exist, you can just rm -rf the directory.

  control> cd ~elabman
  control> mkdir obj-clientside
  control> cd obj-clientside
  control> /path/to/emulab-devel/clientside/configure
  control> make rack-control
  control> sudo make rack-control-install
  control> (cd os/capture; sudo make rack-control-startup-install)

* start capture.

  control> sudo systemctl daemon-reload
  control> sudo systemctl start capture-boss
  control> sudo systemctl start capture-ops

* Stop using the ALWAYSUP state machine for switches, this causes ISUP
  to always get sent, which in certain cases, results in stated
  rebooting the switch!

  Added new ONIE state machine, which handles the way switches actually
  boot into ONIE first and then does the bootinfo/grub dance, or does a
  reload or does admin mode.

* Do not send PXEBOOTING from ONIE; this was a mistake, it throws us
  into the PXEKERNEL state machine, which sometimes results is stated
  rebooting the switch!

  We still use PXEWAIT (it is sent by bootinfod), since that is the
  "waiting" state that is wired into a lot of Emulab, it just happens to
  now be a state in the ONIE state machine, so its legal.

* Fix a bug in libossetup, that was fooling libossetup_switch into
  thinking the wrong thing.

* Add some timeouts to the libosload_mlnx code, sshd sometime refuses to
  answer after a failed login. Strange.

* Fix a fork() problem in the switch reload code; gotta call exit, not
  return! This was wreaking subtle (okay not so subtle) havoc in
  libossetup.

clientside subdir so they can be installed on nodes.

Most important: if a <2TB blockstore has an ext4 filesystem, make sure we
create it without the 64bit and huge_file features. The former will make
it impossible (currently) to take a snapshot since imagezip does not handle
64-bit blocknumbers (working on it...)

Don't stripe an LVM LV over more than 8 devices. Some of the Clemson nodes
have 20+ disks and we won't buy much (and it might even be counterproductive)
to try to stripe writes over all devices all the time.

Still trying to get lvcreate to not prompt when one of the devices has an
old metadata prompt. -Zy is supposed to prevent that, but it doesn't. Try
adding -y as well.

Not related: in the BEGIN block, don't cat $ETCDIR/genvmtype unless it
actually exists. Not everything is a docker container ya know...

(We don't want systemd sending them SIGTERM before bootvnodes can get
them!)

* The primary problem with the mellanox is that the install image does a
  kexec out of ONIE into Linux, spends 30+ minutes doing stuff, and then
  reboots. This throws the reload state machine out of whack cause we do
  not get a chance to send the RELOADDONE state. So ... some change to
  rc.testbed and rc.reload on the USB dongle: the ONIE MFS sends
  RELOADING and writes a flag file to the ONIE partition on the
  "disk" (not the usb). Then the kexec into MLNX, the install happens,
  and reboots. The next boot into ONIE sees the flag file, erases it and
  sends REDLOADDONE. Waits for a bit, and then continues on the normal
  path. This abuses stated in that there a whiny messages in the stated
  log file, but I am immune to stated whining.

* Another item of note is that the switch DHCPs, but only to get the IP
  info, there is no ability to give it an initial config file like we
  can with the Dell switches. The main problem here is that the switch
  comes up with its default login/password which is obviously well known
  cause its in the manual. That means there is a window where the switch
  is vulnerable, but since we block the switches from the public side,
  this is not a serious problem. As soon as we can get in (sshd is
  running) we login and update the config with passwords, keys,
  etc.

* Other changes to the machine dependent osload library module, I had
  done some of this before switching to the Dells way back when, but it
  needed to be updated/completed.

This is necessary for clusters that run an arp lockdown on boss.  This
eluded me for a long time.  None of the documented ways to set the mac
address of an endpoint on container create work (they only work on
post-create network attach).  You have to use some special, weird,
undocumented magic.

(Most of these got lost in some other commit storm, I believe.  The
firewall fixes are new, for newer Dockers that drop traffic by default.)

Turns out we have not been installing (via slicefix) the local site certs
on nodes after they have been imaged. We haven't noticed because we don't
usually use SSL-enabled tmcd. Leigh noticed because we do use it in the
script that locks down ARP entries.

(Also, add support for user to change container entrypoint at runtime.
Note also that the server side now stores the entrypoint/cmd/env
attributes as base64url-encoded virt_node_attributes, so that we can
just use the existing table_regex for those values.)

We add a new runit service (/etc/service/dockerentrypoint) to
clientside/tmcc/linux/docker/dockerfiles/common to handle the
entrypoint/cmd/env/workingdir/user emulation.  From the comments:

  Docker's semantics for ENTRYPOINT/CMD vary depending on if those
  values are specified as arrays of string, or simple as single strings
  (which must be interpreted by /bin/sh -c).

  Handling all the quoting possibilities in the shell is a major pain.
  So, this script handles the basic stuff (in particular, sourcing env
  vars, because we want the shell to interpret them!) -- then execs our
  perl companion script (run.pl) to deal with the entrypoint/command
  files that libvnode_docker::emulabizeImage and
  libvnode_docker::vnodeCreate populated.

  libvnode_docker creates these single-line files in /etc/emulab/docker
  as either string:hexstr(<entrypoint-or-cmd-string>), or
  array:hexstr(a[0]),hexstr(a[1])... .  This allows us to preserve the
  original type of the image's entrypoint/cmd as well as the runtime
  entrypoint/cmd, and to preserve the exact bytes for the eventual final
  call to exec.

  The static files builtin to an emulabized image are
  /etc/emulab/docker/{entrypoint.image,cmd.image}, and those created
  dynamically at runtime if user changes the entrypoint or cmd are
  bind-mounted to /etc/emulab/docker{entrypoint.runtime,cmd.runtime}.

  Given the presence (or absence!) of those files, this script
  implements the emulation, based upon the content in those files.

(Also link the dbus machine-id file to the one systemd will generate on
the next boot.  This seems safe and correct.)

Certain things (like systemd's dhcp client) use the machine-id as a seed
for derived values.  For instance, systemd's dhcp client offers a
ClientIdentifier in the new client style, and some servers will return
the same address to *all* requesting clients, instead of returning only
based on source MAC.  Can't have any of that confusion.

tables from outer Emulab, use dumpuser/newuser since in a target system
setup, we do not do any DB state transfer from the outer Emulab.

Also add partial support for 11.2 MFS (just kernel right now,
binaries are still 10.3).