This post follows the “Multics Simulator Instructions”[1] (with some tweaks) to setup Multics simulator dps8m and run Multics on my Fedora 27. Other Linux distro (Ubuntu/Debian/Raspbian) may need some changes but basically work the same way. Experience the cutting-edge secure operating system made on 1960s by yourself!

1. Install deps – libuv

While libuv can be built from source[2], it would be more easier to install the library using your package manager. For Fedora 27:

dnf install libuv libuv-devel

2. Build the simulator – dps8

Once libuv and its header files are installed, go ahead to build the simulator following the instructions[2]:

git clone git://git.code.sf.net/p/dps8m/code dps8m-code
cd dps8m-code
git checkout R1.0
make

Once the build is done, the dps8 binary can be found under dps8m-code/src/dps8.

3. Run dps8

mkdir -p $HOME/multics/linux
cp $HOME/dps8m-code/src/dps8/dps8 $HOME/multics/linux
cp $HOME/dps8m-code/src/dps8/Devices.txt $HOME/multics/linux
$HOME/multics/linux/dps8

This should start the simulator. Type “quit” to exit the simulator:

[daveti@daveti linux]$ ./dps8
DPS8/M emulator (git b7a50ffc)
Production build
DPS8M system session id is 18555
Please register your system at https://ringzero.wikidot.com/wiki:register
or create the file ‘serial.txt’ containing the line ‘sn: 0’.
FNP telnet server port set to 6180

DPS8M simulator V4.0-0 Beta git commit id: c420925a
sim> quit
Goodbye
[daveti@daveti linux]$

4. Run Multics

Download the QuickStart disk image, unzip it, and mv/rename disk image directory as multics/qs:

wget https://s3.amazonaws.com/eswenson-multics/public/releases/MR12.6f/QuickStart_MR12.6f.zip
unzip $HOME/QuickStart*.zip
mv $HOME/QuickStart_MR12.6f $HOME/multics/qs
cd $HOME/multics/qs
../linux/dps8 MR12.6f_boot.ini

The whole booting process takes a while, but you should be able to see something below if Multics starts correctly:

[daveti@daveti qs]$ ../linux/dps8 MR12.6f_boot.ini
DPS8/M emulator (git b7a50ffc)
Production build
DPS8M system session id is 18555
Please register your system at https://ringzero.wikidot.com/wiki:register
or create the file ‘serial.txt’ containing the line ‘sn: 0’.
FNP telnet server port set to 6180

DPS8M simulator V4.0-0 Beta git commit id: c420925a
TAPE: unit is read only
CONSOLE: ALERT
bootload_0: Booting system MR12.6f generated 01/09/17 1119.1 pst Mon.
0426.6 announce_chwm: 428. pages used of 512. in wired environment.
0426.6 announce_chwm: 706. words used of 1024. in int_unpaged_page_tables.
find_rpv_subsystem: Enter RPV data: M-> [auto-input] rpv a11 ipc 3381 0a

0426.7 load_mst: 946. out of 1048. pages used in disk mst area.
bce (early) 0426.7: M-> [auto-input] bce

Multics Y2K. System was last shudown/ESD at:
Wednesday, January 17, 2018 17:07:31 pst
Current system time is: Wednesday, January 17, 2018 20:26:43 pst.
Is this correct? M-> [auto-input] yes

The current time is more than the supplied boot_delta hours beyond the
unmounted time recorded in the RPV label. Is this correct? M-> [auto-input] yes

bce (boot) 2026.7: M-> [auto-input] yes

bce: Unrecognizable request. Type lr for a list of requests.
bce (boot) 2026.7: M-> [auto-input] boot star

Multics MR12.6f – 01/17/18 2027.0 pst Wed
2027.0 Loading FNP d, >user_dir_dir>SysAdmin>a>mcs.7.6c>site_mcs 7.6c
Received BOOTLOAD command…
listening to 6180
2027.0 FNP d loaded successfully

scavenge_vol: No volumes found
Ready
2027 as as_init_: Multics MR12.6f; Answering Service 17.0
2027 as LOGIN IO.SysDaemon dmn cord (create)
2027 as LOGIN Backup.SysDaemon dmn bk (create)
2027 as LOGIN IO.SysDaemon dmn prta (create)
2027 as LOGIN Utility.SysDaemon dmn ut (create)
2027 as LOGIN Volume_Dumper.Daemon dmn vinc (create)
fnpuv_open_slave 3.31
listening on port 6131
2027 as as_mcs_mpx_: Load signalled for FNP d.
M-> CONSOLE: RELEASED

2027 cord Enter command: coordinator, driver, or logout:
–> cord
2027 bk
2027 prta Enter command: coordinator, driver, or logout:
–> prta
2027 ut copy_dump: Attempt to re-copy an invalid dump.
2027 bk r 20:27 0.446 37
2027 bk
–> bk
2027 vinc
2027 vinc r 20:27 0.450 25
2027 vinc
–> vinc
2027 as sc_admin_command_: Utility.SysDaemon.z: delete_old_pdds
2027 ut send_admin_command: Execution started …
2027 ut completed.
2027 ut monitor_quota: The requested action was not performed.
2027 ut The quota of >dumps is 0, a record limit needs to be specified.
2027 ut
2027 ut Records Left % VTOCEs Left % PB/PD LV Name
2027 ut
2027 ut 166172 100086 60 42218 34130 81 pb root
2027 ut
2027 ut r 20:27 2.481 498
2027 ut
–> ut
2027.2 RCP: Attached tapa_00 for Utility.SysDaemon.z
2027.2 RCP: Detached tapa_00 from Utility.SysDaemon.z
2027.2 RCP: Attached rdra for Utility.SysDaemon.z
2027.2 RCP: Detached rdra from Utility.SysDaemon.z
2027.2 RCP: Attached puna for Utility.SysDaemon.z
2027.2 RCP: Detached puna from Utility.SysDaemon.z
2027.2 RCP: Attached prta for Utility.SysDaemon.z
2027.2 RCP: Detached prta from Utility.SysDaemon.z

Once we have Multics running, we can try to login the system with the help of telnet and the login command in a new terminal. For the first-time login as “Repair” user, the default passwd is “repair”. A new passwd is asked immediately by the system used to replace the old passwd. NOTE: you need to create a new passwd everytime logging into the system! Once logged in, type simple “who” command, and then “logout”:

[daveti@daveti ~]$ telnet localhost 6180
Trying ::1…
telnet: connect to address ::1: Connection refused
Trying 127.0.0.1…
Connected to localhost.
Escape character is ‘^]’.
HSLA Port (d.h000,d.h001,d.h002,d.h003,d.h004,d.h005,d.h006,d.h007,d.h008,d.h009,d.h010,d.h011,d.h012,d.h013,d.h014,d.h015,d.h016,d.h017,d.h018,d.h019,d.h020,d.h021,d.h022,d.h023,d.h024,d.h025,d.h026,d.h027,d.h028,d.h029)?
Attached to line d.h000

Multics MR12.6f: Installation and location (Channel d.h000)
Load = 5.0 out of 90.0 units: users = 5, 01/17/18 2035.3 pst Wed

login Repair -cpw
Password:
New Password:
New Password Again:
Password changed.
You are protected from preemption.
Repair.SysAdmin logged in 01/17/18 2035.6 pst Wed from ASCII terminal “none”.

New messages in message_of_the_day:

Welcome to the Multics System.

print_motd: Created >user_dir_dir>SysAdmin>Repair>Repair.value.
r 20:35 0.469 33

who -a -lg

Multics MR12.6f; Installation and location
Load = 6.0 out of 90.0 units; users = 6, 1 interactive, 5 daemons.
Absentee users = 0 background; Max background absentee users = 3
System up since 01/17/18 2027.0 pst Wed
Last shutdown was at 01/17/18 1707.4 pst Wed

Login at TTY Load User ID

01/17/18 20:27 cord 1.0 IO.SysDaemon
20:27 bk 1.0 Backup.SysDaemon
20:27 prta 1.0 IO.SysDaemon
20:27 ut 1.0 Utility.SysDaemon
20:27 vinc 1.0 Volume_Dumper.Daemon
20:35 none 1.0 Repair.SysAdmin

r 20:36 0.102 3

logout
Repair.SysAdmin logged out 01/17/18 2036.8 pst Wed
CPU usage 1 sec, memory usage 0.1 units, cost $0.07.
hangup
Multics has disconnected you
Connection closed by foreign host.

Meanwhile, you should be able to see the logging information on the Multics ternimal:

CONNECT 127.0.0.1
<>CONNECT 127.0.0.1 to d.h000
2035 as LOGIN Repair.SysAdmin int d.h000 (create)
2036 as LOGOUT Repair.SysAdmin.a int d.h000 0: 0 $0.07 (logo)
DISCONNECT d.d000
CONNECT 127.0.0.1

5. Multics 101

All commands can be found at [3]. Go ahead to try “ls”, “who”, “date”, “time”, and etc. There is also an Emacs available (no Vi apparently). The command mapping between Multics and Linux may also be useful to have a quick understanding of Multics commands[4]. For instance, if you want to take a look at the source file of Multics (HINT: neither B nor C):

cwd >ldd>mcs>source
pr ic_sampler.map355

(Another Hint: Ctrl-C can be your friend~)

6. Now what?

Once we “logout”, it is time to learn how to quit Multics (gracefully). Yes, you need to learn how to quit – take a look at [5] and use 5 ESCs and 5 commands to shutdown Multics:

M-> logout * * *

Ready
M->
CONSOLE: RELEASED

2110 as LOGOUT IO.SysDaemon.z dmn cord 0: 0 $0.03 (looc)
2110 as LOGOUT Backup.SysDaemon.z dmn bk 0: 0 $0.04 (looc)
2110 as LOGOUT IO.SysDaemon.z dmn prta 0: 0 $0.03 (looc)
2110 as LOGOUT Utility.SysDaemon.z dmn ut 0: 3 $1.90 (looc)
2110 as LOGOUT Volume_Dumper.Daemon.z dmn vinc 0: 0 $0.04 (looc)
M-> shut

2110 as act_ctl_: shutdown, 8 0.05 0.05 0.00 0.02 0:3:21 $16.99
2110.9 shutdown complete
DBG(16336227444863)> ERR ERR: Need status register data format
DBG(16336227444911)> ERR ERR: doPayloadChan expected IDCW 10 (12)
bce (boot) 2110.9: M-> die

Do you really wish bce to die? M-> yes

BCE DIS causes CPU halt

simCycles = 16336308761570

cpuCycles = 698896257
Timer runout faults = 21587
Derail faults = 1
Lockup faults = 65
Connect faults = 7242
Illegal procedure faults = 5
Directed fault 0 faults = 754
Directed fault 1 faults = 6926
Access violation faults = 370
Fault tag 2 faults = 3052

Halt, IC: 000012 (000000000000)
sim> quit
Goodbye
[daveti@daveti qs]$

References:

[1] http://multicians.org/sim-inst.html
[2] http://ringzero.wikidot.com/r1-build-from-git
[3] http://multicians.org/multics-commands.html
[4] http://swenson.org/multics_wiki/index.php?title=Linux-to-Multics_Command_Mapping
[5] http://multicians.org/sim-inst-linux.html