usuario74

Yes - this will work
 
# .---------------- minute (0 - 59) # | .------------- hour (0 - 23) # | | .---------- day of month (1 - 31) # | | | .------- month (1 - 12) OR jan,feb,mar,apr ... # | | | | .---- day of week (0 - 6) (Sunday=0 or 7) OR sun,mon,tue,wed,thu,fri,sat # | | | | | # * * * * * command to be executed * 3 * * * /sbin/poweroff  

Not for $20 shipped, but with the -for me - cheap NAS case the NanoPi Neo2 LTS is a option.
The Neo2 is available with 512MB or 1GB of Ram and works fine inside the NAS-Case
(I got 2 of these combinations running over a year).
 
armbian-support for the Neo2 (H5-CPU) is fine. HDMI isnt included, but with the NAS-case he has 2 USB 2.0-Ports, GBE,
a power-switch AND a proper Power-connector for a normal 12V power-supply

Neo2 LTS:
https://www.friendlyarm.com/index.php?route=product/product&path=69&product_id=180

NAS-case:
https://www.friendlyarm.com/index.php?route=product/product&path=85&product_id=222

I am using the "original" Orange Pi cases.
For the smaller Zero-Board the black-cube while adding the Audio-/USB-expansion PCB.
For the "bigger" boards I like the clear ones - but for being only plastic they arent cheap.

hi running armbian ( kernel 4.14 ) and ovpn 2.4.6 and both nanopi neo2 boards.
ovpn is configured with cipher AES-128-CBC and auth SHA256, following results can be seen:

 
top - 04:53:47 up 26 days, 11:42,  2 users,  load average: 0.16, 0.16, 0.09 Tasks: 102 total,   2 running,  57 sleeping,   0 stopped,   0 zombie %Cpu0  :  1.0 us,  1.0 sy,  0.0 ni, 98.0 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 st %Cpu1  :  1.0 us,  2.0 sy,  0.0 ni, 97.0 id,  0.0 wa,  0.0 hi,  0.0 si,  0.0 st %Cpu2  : 20.7 us, 30.1 sy,  0.0 ni, 43.5 id,  0.0 wa,  0.0 hi,  5.7 si,  0.0 st %Cpu3  :  0.3 us,  0.3 sy,  0.0 ni, 99.0 id,  0.0 wa,  0.0 hi,  0.3 si,  0.0 st KiB Mem :   494152 total,   128980 free,    92528 used,   272644 buff/cache KiB Swap:   247072 total,   229664 free,    17408 used.   382416 avail Mem   PID USER      PR  NI    VIRT    RES    SHR S  %CPU %MEM     TIME+ COMMAND  1191 root      20   0   10180   6132   5324 R  59.1  1.2 137:16.90 openvpn  
and following with single thread " iperf3 -4 -V -c 192.168.10.2 -t 60 -b 0 -P 1 "
 
iperf 3.1.3 Linux vpn01 4.14.70-sunxi64 #274 SMP Wed Sep 19 12:09:30 CEST 2018 aarch64 Time: Sun, 09 Dec 2018 02:53:07 GMT Connecting to host 192.168.10.2, port 5201       Cookie: vpn01.1544323987.071807.somewhat       TCP MSS: 1276 (default) [  4] local 10.8.0.2 port 63472 connected to 192.168.10.2 port 5201 Starting Test: protocol: TCP, 1 streams, 131072 byte blocks, omitting 0 seconds, 60 second test [ ID] Interval           Transfer     Bandwidth       Retr  Cwnd [  4]   0.00-1.00   sec  9.07 MBytes  75.9 Mbits/sec  199   1.24 MBytes [  4]   1.00-2.00   sec  8.75 MBytes  73.4 Mbits/sec  166   1.09 MBytes [  4]   2.00-3.00   sec  12.5 MBytes   105 Mbits/sec    0   1.35 MBytes [  4]   3.00-4.00   sec  7.50 MBytes  62.9 Mbits/sec    0   1.36 MBytes [  4]   4.00-5.00   sec  7.50 MBytes  62.9 Mbits/sec   54   1.22 MBytes [  4]   5.00-6.00   sec  8.75 MBytes  73.4 Mbits/sec    0   1.22 MBytes [  4]   6.00-7.00   sec  7.50 MBytes  62.8 Mbits/sec    0   1.24 MBytes [  4]   7.00-8.00   sec  8.75 MBytes  73.5 Mbits/sec    0   1.16 MBytes [  4]   8.00-9.00   sec  8.75 MBytes  73.3 Mbits/sec    0   1.21 MBytes [  4]   9.00-10.00  sec  11.2 MBytes  94.4 Mbits/sec    0   1.41 MBytes [  4]  10.00-11.00  sec  8.75 MBytes  73.4 Mbits/sec    3   1.59 MBytes [  4]  11.00-12.00  sec  7.50 MBytes  63.0 Mbits/sec   46   1.58 MBytes [  4]  12.00-13.00  sec  10.0 MBytes  83.9 Mbits/sec    0   1.27 MBytes [  4]  13.00-14.00  sec  7.50 MBytes  62.9 Mbits/sec   25   1.17 MBytes [  4]  14.00-15.00  sec  11.2 MBytes  94.4 Mbits/sec    0   1.40 MBytes [  4]  15.00-16.00  sec  11.2 MBytes  94.4 Mbits/sec   15    616 KBytes [  4]  16.00-17.00  sec  6.25 MBytes  52.4 Mbits/sec    9   1.25 MBytes [  4]  17.00-18.00  sec  8.75 MBytes  73.4 Mbits/sec  252   1.15 MBytes [  4]  18.00-19.00  sec  7.50 MBytes  62.9 Mbits/sec    0   1.24 MBytes [  4]  19.00-20.00  sec  10.0 MBytes  83.8 Mbits/sec   29    684 KBytes [  4]  20.00-21.00  sec  7.50 MBytes  62.9 Mbits/sec    0   1.24 MBytes [  4]  21.00-22.00  sec  7.50 MBytes  62.9 Mbits/sec  194   1.26 MBytes [  4]  22.00-23.00  sec  8.75 MBytes  73.4 Mbits/sec    0   1.25 MBytes [  4]  23.00-24.00  sec  7.50 MBytes  62.9 Mbits/sec    0   1.16 MBytes [  4]  24.00-25.00  sec  12.5 MBytes   105 Mbits/sec    0   1.43 MBytes [  4]  25.00-26.00  sec  6.25 MBytes  52.4 Mbits/sec   46   1.42 MBytes [  4]  26.00-27.00  sec  8.75 MBytes  73.4 Mbits/sec    0   1.40 MBytes [  4]  27.00-28.00  sec  8.75 MBytes  73.4 Mbits/sec   18   1.24 MBytes [  4]  28.00-29.00  sec  8.75 MBytes  73.4 Mbits/sec    0   1.23 MBytes [  4]  29.00-30.00  sec  10.0 MBytes  83.9 Mbits/sec    0   1.37 MBytes [  4]  30.00-31.00  sec  7.50 MBytes  62.9 Mbits/sec    0   1.26 MBytes [  4]  31.00-32.00  sec  8.75 MBytes  73.4 Mbits/sec   64   1.15 MBytes [  4]  32.00-33.00  sec  8.75 MBytes  73.4 Mbits/sec    0   1.16 MBytes [  4]  33.00-34.00  sec  10.0 MBytes  83.9 Mbits/sec    0   1.34 MBytes [  4]  34.00-35.00  sec  8.75 MBytes  73.4 Mbits/sec    0   1.34 MBytes [  4]  35.00-36.00  sec  8.75 MBytes  73.4 Mbits/sec    0   1.26 MBytes [  4]  36.00-37.00  sec  8.75 MBytes  73.4 Mbits/sec    0   1.29 MBytes [  4]  37.00-38.00  sec  8.75 MBytes  73.4 Mbits/sec    0   1.25 MBytes [  4]  38.00-39.00  sec  7.50 MBytes  62.9 Mbits/sec    0   1.25 MBytes [  4]  39.00-40.00  sec  10.0 MBytes  83.8 Mbits/sec    0   1.16 MBytes [  4]  40.00-41.00  sec  11.2 MBytes  94.4 Mbits/sec    0   1.37 MBytes [  4]  41.00-42.00  sec  10.0 MBytes  83.9 Mbits/sec    0   1.38 MBytes [  4]  42.00-43.00  sec  7.50 MBytes  63.0 Mbits/sec   79   1.07 MBytes [  4]  43.00-44.00  sec  8.75 MBytes  73.4 Mbits/sec   34    728 KBytes [  4]  44.00-45.00  sec  7.50 MBytes  62.9 Mbits/sec   99   1.38 MBytes [  4]  45.00-46.00  sec  7.50 MBytes  62.9 Mbits/sec  200   1.38 MBytes [  4]  46.00-47.00  sec  8.75 MBytes  73.4 Mbits/sec   62   1.21 MBytes [  4]  47.00-48.00  sec  7.50 MBytes  62.9 Mbits/sec   22   1.26 MBytes [  4]  48.00-49.00  sec  8.75 MBytes  73.5 Mbits/sec    0   1.33 MBytes [  4]  49.00-50.00  sec  8.75 MBytes  73.4 Mbits/sec    5   1.23 MBytes [  4]  50.00-51.00  sec  7.50 MBytes  62.8 Mbits/sec    0   1.25 MBytes [  4]  51.00-52.00  sec  10.0 MBytes  84.0 Mbits/sec    0   1.30 MBytes [  4]  52.00-53.00  sec  7.50 MBytes  62.9 Mbits/sec    0   1.29 MBytes [  4]  53.00-54.00  sec  8.75 MBytes  73.4 Mbits/sec    4   1.26 MBytes [  4]  54.00-55.00  sec  7.50 MBytes  62.9 Mbits/sec    0   1.24 MBytes [  4]  55.00-56.00  sec  8.75 MBytes  73.4 Mbits/sec    0   1.23 MBytes [  4]  56.00-57.00  sec  7.50 MBytes  62.9 Mbits/sec    0   1.19 MBytes [  4]  57.00-58.00  sec  10.0 MBytes  83.9 Mbits/sec    0   1.23 MBytes [  4]  58.00-59.00  sec  7.50 MBytes  62.9 Mbits/sec    0   1.21 MBytes [  4]  59.00-60.00  sec  6.25 MBytes  52.4 Mbits/sec    0   1.24 MBytes - - - - - - - - - - - - - - - - - - - - - - - - - Test Complete. Summary Results: [ ID] Interval           Transfer     Bandwidth       Retr [  4]   0.00-60.00  sec   520 MBytes  72.7 Mbits/sec  1625             sender [  4]   0.00-60.00  sec   514 MBytes  71.8 Mbits/sec                  receiver CPU Utilization: local/sender 1.5% (0.1%u/1.3%s), remote/receiver 3.5% (0.4%u/3.2%s) iperf Done.  
 
also did not tweak kernel settings too much atm - both ends read:
net.core.default_qdisc = fq_codel net.core.netdev_max_backlog = 1024 net.core.rmem_max = 33554432 net.core.wmem_max = 33554432 net.ipv4.tcp_rmem = 4096 87380 33554432 net.ipv4.tcp_wmem = 4096 87380 33554432 net.ipv4.tcp_congestion_control = bbr # RETEST westwood OR cubic net.ipv4.tcp_max_syn_backlog = 1024 net.ipv4.tcp_slow_start_after_idle = 0 net.ipv4.tcp_no_metrics_save = 0 net.ipv4.ip_local_port_range = 9000 65535  
If you want a cheap and low wattage VPN consider H5 boards ( eg nanopi neo2 or orange pi zero plus2 ) that should handle proper TV streaming (15-20Mbit) over ovpn this is your option.
If speed will be most important consider other platforms, I'm currently looking in to the ASRock J4005B-ITX and should do 300Mbit ...

I can only reply to question 4 and based on my limited sample of one: I bought their power supply with mi orange pi pc and it's been working 24/7 for the last year and half. Crossing fingers....

It is. With recent kernel which in the development.

Gigabit does not make sense. I'm afraid you will not get more than 20mbps out of your board. This is a very very optimistic expectation,  10 is a more realistic number.  OpenVPN is secure but there is a significant overhead. 
 
Having a hardware encryption can make your board slightly faster probably, but definitely will make it cooler. 

You should also consider processor speed and whether the kernel supports HW crypto acceleration. I have tried openvpn both in an OrangePi+ 2e (Allwinner H3), and an Odroid XU4, and performance is an order of magnitude faster in the XU4.
 
H5 has ARMv8 crypto extensions, so just make sure you choose a kernel that supports them.

Hello!
 
Bigger boards = better heat dispersion and (better) voltage control = less (over)heating, better (non microUSB) powering = better stability. H5 is noticable faster than H3 and has better software support than A64 => IMO Opi PC2 should fit your needs.