Groups | Search | Server Info | Login | Register


Groups > alt.sys.pdp10 > #9856

Re: Try again: IP between Pi <--> klh10 TOPS-20

From jayjwa <jayjwa@atr2.ath.cx.invalid>
Newsgroups alt.sys.pdp10
Subject Re: Try again: IP between Pi <--> klh10 TOPS-20
Date 2026-01-03 12:15 -0500
Organization atr2net 2026
Message-ID <871pk6mxd0.fsf@atr2.ath.cx> (permalink)
References (2 earlier) <mddldij8lyb.fsf@panix5.panix.com> <87fr8qfsmp.fsf@atr2.ath.cx> <36bf44a9-b22b-4529-8b69-c3b5598f6a04@gmail.com> <87ldih48o8.fsf@atr2.ath.cx> <fc5af379-0925-4d89-b674-ea3da6ab3db1@gmail.com>

Show all headers | View raw


David Todd <hdtodd@gmail.com> writes:

> 	- Pi eth0 is .88; wlan0 is .89
> 	- DEC20 is to be .62 from <system>internet.address
> 	- br0 will have address .62
> 	- tap0 will have no address

> ; Set Ethernet address
> devdef ni0 564 ni20 dedic=true ifmeth=tap ifc=tap0 decnet=true
Seems OK.

> $cat internet.address
> IPNI#0,192.168.1.62,PACKET-SIZE:1500,LOGICAL-HOST-MASK:255.255.255.0,DEFAULT,PREFERRED
> $cat internet.gateways
> PRIME 192.168.1.1
No. Gateway would be the br0 address which you have as .62.
 ip -c addr show br0
5: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether aa:00:04:00:01:04 brd ff:ff:ff:ff:ff:ff
    inet 192.168.20.1/24 brd 192.168.20.255 scope global br0
       valid_lft forever preferred_lft forever

$type <system>internet.address
IPNI#0,192.168.20.8,PACKET-SIZE:1500,LOGICAL-HOST-MASK:255.0.0.0,DEFAULT,PREFERR
ED
$type <system>internet.gateways
PRIME 192.168.20.1
$
Looks like you have TOPS-20 trying to take br0's
ip4. <system>internet.gateways and br0 are the same addr, IPNI#0 is
TOPS-20. You can't put the same ip4 on both TOPS-20 and br0. 

> I modified my br0+tap0 setup to set the route for br0 as you suggested:
>
> + ip link add name br0 type bridge
> + ip link set br0 type bridge stp_state 1
> + ip link set br0 up
> + ip -4 addr add 192.168.1.62/24 broadcast + dev br0
> + ip r add default via 192.168.1.1 proto static src 192.168.1.62 dev br0
>
> + ip tuntap add dev tap0 mode tap
> + ip link set dev tap0 master br0
> + ip link set tap0 up
So .1.1 is your router? This is confusing because I think you have an
extra piece of hardware in here than in my setup. 

> As soon as br0 is brought up, Pi connectivity with the LAN
> is lost.  As soon as br0 is brought down, Pi connectivity
> with the LAN is restored.
Looks like a routing issue, and two different systems/interfaces are
trying to take .62.

> and trying to get to the LAN from the Pi side fails:
> (BUT NOTICE THAT IT'S *FROM* .62, not .88 or .89!):
>
> hdtodd@pi-5:~ $ ping hdt
> PING hdt-h (192.168.1.50) 56(84) bytes of data.
> From pi20 (192.168.1.62) icmp_seq=1 Destination Host Unreachable
This might be from two systems sharing the .62.

> After booting the DEC20, the network looks like this
> (note that tap0 and br0 have the same MAC address; is that right?):
No. They should have their own. The tap0 one doesn't matter as long as
it's unique.

ip -c link show br0
5: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000
    link/ether aa:00:04:00:01:04 brd ff:ff:ff:ff:ff:ff

ip -c link show tap10
16: tap10: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br0 state UP mode DEFAULT group default qlen 1000
    link/ether 22:47:39:cb:f5:ba brd ff:ff:ff:ff:ff:ff

For DECnet, br0 gets 1.1 and TOPS-20 (inside the system itself) gets
1.19, AA:00:04:00:13:04. Eventually, you'll probably want DECnet so best
to plan for it now.


> KLH10# devdef ni0 564 ni20 dedic=true ifmeth=tap ifc=tap0 decnet=true
You might try the macvlan off the eth0 approach. Something like
devdef ni0 564 ni20 dedic=true ifmeth=pcap ifc=macvlan0 decnet=true

My PyDECnet uses it and PyDECnet can see other (DECnet) nodes.
# ip -c link add name macvlan0 link eth0 type macvlan
# ip -c link set dev macvlan0 address AA:00:04:00:02:04
# ip -c link set macvlan0 up
circuit macvlan-0 Ethernet pcap:macvlan0 --mop

I never tried this way with KLH10 but it should send IP and DEC DNA as
well. You might have to play with the config a bit.

> % [Logger  2-Jan-2026 15:52:54 ]: Started at  2-Jan-2026 15:52:53
> SJ  0:
> SJ  0: 15:52:53 	  -- Too many operator LOG files --
> SJ  0: 		Current LOG file will be appended
Logs need trimming?
$dir <spool>

   TOPS20:<SPOOL>
 OPERATOR-SYSTEM.LOG.3
 OPERATOR-SYSTEM-LOG.000.2
 PRIMARY-MASTER-QUEUE-FILE.QUASAR.1

 Total of 8 pages in 3 files

>  Job  Line Program  User              Origin
>    8*    5  SYSTAT  HDTODD
>
>    1    13  OPR     OPERATOR
>    2   DET  SYSJB1  OPERATOR
>    3    14  RESOLV  OPERATOR
>    4    15  NETSRV  OPERATOR
>    5    16  SMTJFN  OPERATOR
>    6    17  MMAILR  OPERATOR
>    7    20  IMAPSV  OPERATOR
If you want DECmail later, you have to add MX and a few
logicals/directories.

> $info inter
>  Network Todds.Comcast.net host name is pi20
>  Network interface type is IPNI, Internet address is 192.168.1.62
>  Network interface is up, output is enabled
>  Network service is enabled
>  Last network interface up transition: 2-Jan-2026 15:52:52
Looks like two interfaces are trying to use .62:

> 	- DEC20 is to be .62 from <system>internet.address
> 	- br0 will have address .62

-- 
PGP Key ID: 781C A3E2 C6ED 70A6 B356  7AF5 B510 542E D460 5CAE
       "The Internet should always be the Wild West!"

Back to alt.sys.pdp10 | Previous | NextPrevious in thread | Next in thread | Find similar


Thread

Try again: IP between Pi <--> klh10 TOPS-20 David Todd <HDTodd@gmail.com> - 2025-12-29 18:31 -0500
  Re: Try again: IP between Pi <--> klh10 TOPS-20 jayjwa <jayjwa@atr2.ath.cx.invalid> - 2025-12-30 12:54 -0500
    Re: Try again: IP between Pi <--> klh10 TOPS-20 Rich Alderson <news@alderson.users.panix.com> - 2025-12-30 20:43 -0500
      Re: Try again: IP between Pi <--> klh10 TOPS-20 jayjwa <jayjwa@atr2.ath.cx.invalid> - 2025-12-31 12:50 -0500
        Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <HDTodd@gmail.com> - 2026-01-01 09:59 -0500
          Re: Try again: IP between Pi <--> klh10 TOPS-20 jayjwa <jayjwa@atr2.ath.cx.invalid> - 2026-01-01 11:08 -0500
            Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <HDTodd@gmail.com> - 2026-01-01 11:27 -0500
              Re: Try again: IP between Pi <--> klh10 TOPS-20 jayjwa <jayjwa@atr2.ath.cx.invalid> - 2026-01-02 13:04 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-02 17:36 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-01-03 05:37 +0000
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <HDTodd@gmail.com> - 2026-01-03 07:09 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-03 08:40 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 jayjwa <jayjwa@atr2.ath.cx.invalid> - 2026-01-03 11:33 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <HDTodd@gmail.com> - 2026-01-03 06:59 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-04 09:07 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-04 09:20 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 Johnny Billquist <bqt@softjar.se> - 2026-01-04 16:26 +0100
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-04 10:57 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 Lawrence D’Oliveiro <ldo@nz.invalid> - 2026-01-05 06:38 +0000
            Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-02 07:46 -0500
              Re: Try again: IP between Pi <--> klh10 TOPS-20 jayjwa <jayjwa@atr2.ath.cx.invalid> - 2026-01-02 12:54 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-02 17:05 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 Rich Alderson <news@alderson.users.panix.com> - 2026-01-02 20:32 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <HDTodd@gmail.com> - 2026-01-02 22:21 -0500
            Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-02 17:47 -0500
              Re: Try again: IP between Pi <--> klh10 TOPS-20 jayjwa <jayjwa@atr2.ath.cx.invalid> - 2026-01-03 12:15 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-03 16:57 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-03 17:00 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 jayjwa <jayjwa@atr2.ath.cx.invalid> - 2026-01-04 11:21 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <HDTodd@gmail.com> - 2026-01-05 17:52 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <HDTodd@gmail.com> - 2026-01-05 18:13 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 jayjwa <jayjwa@atr2.ath.cx.invalid> - 2026-01-06 12:53 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <HDTodd@gmail.com> - 2026-01-06 18:12 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <HDTodd@gmail.com> - 2026-01-06 18:15 -0500
                MM vs. MS/MX [was Re: Try again: IP between Pi <--> klh10 TOPS-20] Rich Alderson <news@alderson.users.panix.com> - 2026-01-07 18:28 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-03 17:07 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 jayjwa <jayjwa@atr2.ath.cx.invalid> - 2026-01-04 11:28 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-04 13:52 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-03 18:12 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 scott@slp53.sl.home (Scott Lurndal) - 2026-01-04 00:00 +0000
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-04 08:48 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 scott@slp53.sl.home (Scott Lurndal) - 2026-01-04 16:00 +0000
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-04 14:02 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 jayjwa <jayjwa@atr2.ath.cx.invalid> - 2026-01-04 11:56 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-04 14:21 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 jayjwa <jayjwa@atr2.ath.cx.invalid> - 2026-01-04 16:16 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-04 16:58 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-04 14:28 -0500
                Re: Try again: IP between Pi <--> klh10 TOPS-20 scott@slp53.sl.home (Scott Lurndal) - 2026-01-05 15:33 +0000
                Re: Try again: IP between Pi <--> klh10 TOPS-20 Andy Valencia <vandys@vsta.org> - 2026-01-05 15:45 -0800
                Re: Try again: IP between Pi <--> klh10 TOPS-20 David Todd <hdtodd@gmail.com> - 2026-01-04 08:59 -0500

csiph-web