subject:"\[LEDE\-DEV\] DHCP via bridge in case of IPv4"

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

2016-08-15 Thread Alexey Brodkin

Hello,

On Mon, 2016-07-11 at 06:15 +, Alexey Brodkin wrote:
> Hi Russel,
> 
> On Sun, 2016-07-10 at 00:19 -0700, Russell Senior wrote:
> > 
> > > > > > > "Alexey" == Alexey Brodkin  writes:
> > Alexey> Hi Aaron,
> > Alexey> On Sat, 2016-07-09 at 07:47 -0400, Aaron Z wrote:
> > > 
> > > > On Sat, Jul 9, 2016 at 4:37 AM, Alexey Brodkin
> > > >  wrote:
> > > > > 
> > > > > Hello,
> > > > > 
> > > > > I was playing with quite simple bridged setup on different boards
> > > > with > very recent kernels (4.6.3 as of this writing) and found one
> > > > interesting > behavior that I cannot yet understand and googling
> > > > din't help here as well.
> > > > > 
> > > > > My setup is pretty simple: >
> > > > -   --   -
> > > > > 
> > > > > > HOST  |   | "Dumb AP"  |   | Wireless
> > > > client   | > > with DHCP |<->(eth0) (wlan0)<->|
> > > > attempting to | > > server|   |\ br0
> > > > / |   | get settings via DHCP | >
> > > > -   --   -
> > > > > * HOST is my laptop with DHCP server that works for sure.  > *
> > > > "Dumb AP" is a separate board (I tried ARM-based Wandboard and
> > > > ARC-based >   AXS10x boards but results are exactly the same) with
> > > > wired (eth0) and wireless >   (wlan0) network controllers bridged
> > > > together (br0). That "br0" bridge flawlessly >   gets its settings
> > > > from DHCP server on host.  > * Wireless client could be either a
> > > > smatrphone or another laptop etc but >   what's important it should
> > > > be configured to get network settings by DHCP as well.
> > > > > 
> > > > > So what happens "br0" always gets network settings from DHCP server
> > > > on HOST.  > That's fine. But wireless client only reliably gets
> > > > settings from DHCP server > if IPv6 is enabled on "Dumb AP" board. If
> > > > IPv6 is disabled I may see that > wireless client sends "DHCP
> > > > Discover" then server replies with "DHCP Offer" but > that offer
> > > > never reaches wireless client.
> > > > 
> > > > Do you have WDS enabled? If not, DHCP has issues in that scenario:
> > > > https://wiki.openwrt.org/doc/howto/clientmode
> > If the Dumb AP's wireless interface is in ap-mode, then this shouldn't
> > be an issue.  It's only client-mode interfaces that have trouble with 
> > bridging.
> > 
> > I'd suggest running tcpdump on the Dumb AP's wireless interface and the
> > client's wireless interface and see which of them sees the various parts
> > of the DHCP handshake.
> 
> So I did but for DHCP server and wireless client (had no tcpdump on Dump AP
> at the moment).
> 
> That's what I see on the server:
> ->8---
> No. TimeSource Destination  Protocol Length Info
>  3 0.151181000  0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 11 2.760796000  10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
> Transaction ID 0x31dc321f
> 14 5.220985000  0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 15 5.22115  10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
> Transaction ID 0x31dc321f
> 23 15.649835000 0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 24 15.650017000 10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
> Transaction ID 0x31dc321f
> 32 25.648589000 0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 33 25.648758000 10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
> Transaction ID 0x31dc321f
> 43 35.864567000 0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 48 38.832837000 10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
> Transaction ID 0x31dc321f
> ->8---
> 
> That's on the wireless client:
> ->8---
> No.  Time   Source   Destination  Protocol Length Info
> 1171 94.192971000   0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 1182 99.263686000   0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 1185 109.692642000  0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 1186 119.691474000  0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 1190 129.907507000  0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> ->8---
> 
> I'll try to capture data from Dumb AP sometime soon and will reply to the 
> thread.

So finally after quite some time I figured out what

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

2016-08-15 Thread Alexey Brodkin

Hello,

On Mon, 2016-07-11 at 06:15 +, Alexey Brodkin wrote:
> Hi Russel,
> 
> On Sun, 2016-07-10 at 00:19 -0700, Russell Senior wrote:
> > 
> > > > > > > "Alexey" == Alexey Brodkin  writes:
> > Alexey> Hi Aaron,
> > Alexey> On Sat, 2016-07-09 at 07:47 -0400, Aaron Z wrote:
> > > 
> > > > On Sat, Jul 9, 2016 at 4:37 AM, Alexey Brodkin
> > > >  wrote:
> > > > > 
> > > > > Hello,
> > > > > 
> > > > > I was playing with quite simple bridged setup on different boards
> > > > with > very recent kernels (4.6.3 as of this writing) and found one
> > > > interesting > behavior that I cannot yet understand and googling
> > > > din't help here as well.
> > > > > 
> > > > > My setup is pretty simple: >
> > > > -   --   -
> > > > > 
> > > > > > HOST  |   | "Dumb AP"  |   | Wireless
> > > > client   | > > with DHCP |<->(eth0) (wlan0)<->|
> > > > attempting to | > > server|   |\ br0
> > > > / |   | get settings via DHCP | >
> > > > -   --   -
> > > > > * HOST is my laptop with DHCP server that works for sure.  > *
> > > > "Dumb AP" is a separate board (I tried ARM-based Wandboard and
> > > > ARC-based >   AXS10x boards but results are exactly the same) with
> > > > wired (eth0) and wireless >   (wlan0) network controllers bridged
> > > > together (br0). That "br0" bridge flawlessly >   gets its settings
> > > > from DHCP server on host.  > * Wireless client could be either a
> > > > smatrphone or another laptop etc but >   what's important it should
> > > > be configured to get network settings by DHCP as well.
> > > > > 
> > > > > So what happens "br0" always gets network settings from DHCP server
> > > > on HOST.  > That's fine. But wireless client only reliably gets
> > > > settings from DHCP server > if IPv6 is enabled on "Dumb AP" board. If
> > > > IPv6 is disabled I may see that > wireless client sends "DHCP
> > > > Discover" then server replies with "DHCP Offer" but > that offer
> > > > never reaches wireless client.
> > > > 
> > > > Do you have WDS enabled? If not, DHCP has issues in that scenario:
> > > > https://wiki.openwrt.org/doc/howto/clientmode
> > If the Dumb AP's wireless interface is in ap-mode, then this shouldn't
> > be an issue.  It's only client-mode interfaces that have trouble with 
> > bridging.
> > 
> > I'd suggest running tcpdump on the Dumb AP's wireless interface and the
> > client's wireless interface and see which of them sees the various parts
> > of the DHCP handshake.
> 
> So I did but for DHCP server and wireless client (had no tcpdump on Dump AP
> at the moment).
> 
> That's what I see on the server:
> ->8---
> No. TimeSource Destination  Protocol Length Info
>  3 0.151181000  0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 11 2.760796000  10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
> Transaction ID 0x31dc321f
> 14 5.220985000  0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 15 5.22115  10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
> Transaction ID 0x31dc321f
> 23 15.649835000 0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 24 15.650017000 10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
> Transaction ID 0x31dc321f
> 32 25.648589000 0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 33 25.648758000 10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
> Transaction ID 0x31dc321f
> 43 35.864567000 0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 48 38.832837000 10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
> Transaction ID 0x31dc321f
> ->8---
> 
> That's on the wireless client:
> ->8---
> No.  Time   Source   Destination  Protocol Length Info
> 1171 94.192971000   0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 1182 99.263686000   0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 1185 109.692642000  0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 1186 119.691474000  0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> 1190 129.907507000  0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
> Transaction ID 0x31dc321f
> ->8---
> 
> I'll try to capture data from Dumb AP sometime soon and will reply to the 
> thread.

So finally after quite some time I figured out what happens in my setup.
Basically it all boils down to the

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

2016-07-11 Thread Alexey Brodkin

Hi Russel,

On Sun, 2016-07-10 at 00:19 -0700, Russell Senior wrote:
> > 
> > > 
> > > > 
> > > > > 
> > > > > > 
> > > > > > "Alexey" == Alexey Brodkin  writes:
> Alexey> Hi Aaron,
> Alexey> On Sat, 2016-07-09 at 07:47 -0400, Aaron Z wrote:
> > 
> > > 
> > > On Sat, Jul 9, 2016 at 4:37 AM, Alexey Brodkin
> > >  wrote:
> > > > 
> > > > 
> > > > Hello,
> > > > 
> > > > I was playing with quite simple bridged setup on different boards
> > > with > very recent kernels (4.6.3 as of this writing) and found one
> > > interesting > behavior that I cannot yet understand and googling
> > > din't help here as well.
> > > > 
> > > > 
> > > > My setup is pretty simple: >
> > > -   --   -
> > > > 
> > > > > 
> > > > > 
> > > > > HOST  |   | "Dumb AP"  |   | Wireless
> > > client   | > > with DHCP |<->(eth0) (wlan0)<->|
> > > attempting to | > > server|   |\ br0
> > > / |   | get settings via DHCP | >
> > > -   --   -
> > > > 
> > > > 
> > > > * HOST is my laptop with DHCP server that works for sure.  > *
> > > "Dumb AP" is a separate board (I tried ARM-based Wandboard and
> > > ARC-based >   AXS10x boards but results are exactly the same) with
> > > wired (eth0) and wireless >   (wlan0) network controllers bridged
> > > together (br0). That "br0" bridge flawlessly >   gets its settings
> > > from DHCP server on host.  > * Wireless client could be either a
> > > smatrphone or another laptop etc but >   what's important it should
> > > be configured to get network settings by DHCP as well.
> > > > 
> > > > 
> > > > So what happens "br0" always gets network settings from DHCP server
> > > on HOST.  > That's fine. But wireless client only reliably gets
> > > settings from DHCP server > if IPv6 is enabled on "Dumb AP" board. If
> > > IPv6 is disabled I may see that > wireless client sends "DHCP
> > > Discover" then server replies with "DHCP Offer" but > that offer
> > > never reaches wireless client.
> > > 
> > > 
> > > Do you have WDS enabled? If not, DHCP has issues in that scenario:
> > > https://wiki.openwrt.org/doc/howto/clientmode
> If the Dumb AP's wireless interface is in ap-mode, then this shouldn't
> be an issue.  It's only client-mode interfaces that have trouble with 
> bridging.
> 
> I'd suggest running tcpdump on the Dumb AP's wireless interface and the
> client's wireless interface and see which of them sees the various parts
> of the DHCP handshake.

So I did but for DHCP server and wireless client (had no tcpdump on Dump AP
at the moment).

That's what I see on the server:
->8---
No. TimeSource Destination  Protocol Length Info
 3 0.151181000  0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
11 2.760796000  10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
Transaction ID 0x31dc321f
14 5.220985000  0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
15 5.22115  10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
Transaction ID 0x31dc321f
23 15.649835000 0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
24 15.650017000 10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
Transaction ID 0x31dc321f
32 25.648589000 0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
33 25.648758000 10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
Transaction ID 0x31dc321f
43 35.864567000 0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
48 38.832837000 10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
Transaction ID 0x31dc321f
->8---

That's on the wireless client:
->8---
No.  Time   Source   Destination  Protocol Length Info
1171 94.192971000   0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
1182 99.263686000   0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
1185 109.692642000  0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
1186 119.691474000  0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
1190 129.907507000  0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
->8---

I'll try to capture data from Dumb AP sometime soon and will reply to the 
thread.

-Alexey

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

2016-07-11 Thread Alexey Brodkin

Hi Russel,

On Sun, 2016-07-10 at 00:19 -0700, Russell Senior wrote:
> > 
> > > 
> > > > 
> > > > > 
> > > > > > 
> > > > > > "Alexey" == Alexey Brodkin  writes:
> Alexey> Hi Aaron,
> Alexey> On Sat, 2016-07-09 at 07:47 -0400, Aaron Z wrote:
> > 
> > > 
> > > On Sat, Jul 9, 2016 at 4:37 AM, Alexey Brodkin
> > >  wrote:
> > > > 
> > > > 
> > > > Hello,
> > > > 
> > > > I was playing with quite simple bridged setup on different boards
> > > with > very recent kernels (4.6.3 as of this writing) and found one
> > > interesting > behavior that I cannot yet understand and googling
> > > din't help here as well.
> > > > 
> > > > 
> > > > My setup is pretty simple: >
> > > -   --   -
> > > > 
> > > > > 
> > > > > 
> > > > > HOST  |   | "Dumb AP"  |   | Wireless
> > > client   | > > with DHCP |<->(eth0) (wlan0)<->|
> > > attempting to | > > server|   |\ br0
> > > / |   | get settings via DHCP | >
> > > -   --   -
> > > > 
> > > > 
> > > > * HOST is my laptop with DHCP server that works for sure.  > *
> > > "Dumb AP" is a separate board (I tried ARM-based Wandboard and
> > > ARC-based >   AXS10x boards but results are exactly the same) with
> > > wired (eth0) and wireless >   (wlan0) network controllers bridged
> > > together (br0). That "br0" bridge flawlessly >   gets its settings
> > > from DHCP server on host.  > * Wireless client could be either a
> > > smatrphone or another laptop etc but >   what's important it should
> > > be configured to get network settings by DHCP as well.
> > > > 
> > > > 
> > > > So what happens "br0" always gets network settings from DHCP server
> > > on HOST.  > That's fine. But wireless client only reliably gets
> > > settings from DHCP server > if IPv6 is enabled on "Dumb AP" board. If
> > > IPv6 is disabled I may see that > wireless client sends "DHCP
> > > Discover" then server replies with "DHCP Offer" but > that offer
> > > never reaches wireless client.
> > > 
> > > 
> > > Do you have WDS enabled? If not, DHCP has issues in that scenario:
> > > https://wiki.openwrt.org/doc/howto/clientmode
> If the Dumb AP's wireless interface is in ap-mode, then this shouldn't
> be an issue.  It's only client-mode interfaces that have trouble with 
> bridging.
> 
> I'd suggest running tcpdump on the Dumb AP's wireless interface and the
> client's wireless interface and see which of them sees the various parts
> of the DHCP handshake.

So I did but for DHCP server and wireless client (had no tcpdump on Dump AP
at the moment).

That's what I see on the server:
->8---
No. TimeSource Destination  Protocol Length Info
 3 0.151181000  0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
11 2.760796000  10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
Transaction ID 0x31dc321f
14 5.220985000  0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
15 5.22115  10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
Transaction ID 0x31dc321f
23 15.649835000 0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
24 15.650017000 10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
Transaction ID 0x31dc321f
32 25.648589000 0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
33 25.648758000 10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
Transaction ID 0x31dc321f
43 35.864567000 0.0.0.0255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
48 38.832837000 10.42.0.1  10.42.0.13   DHCP 342DHCP Offer- 
Transaction ID 0x31dc321f
->8---

That's on the wireless client:
->8---
No.  Time   Source   Destination  Protocol Length Info
1171 94.192971000   0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
1182 99.263686000   0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
1185 109.692642000  0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
1186 119.691474000  0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
1190 129.907507000  0.0.0.0  255.255.255.255  DHCP 342DHCP Discover - 
Transaction ID 0x31dc321f
->8---

I'll try to capture data from Dumb AP sometime soon and will reply to the 
thread.

-Alexey

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

2016-07-10 Thread Russell Senior

> "Alexey" == Alexey Brodkin  writes:

Alexey> Hi Aaron,
Alexey> On Sat, 2016-07-09 at 07:47 -0400, Aaron Z wrote:
>> On Sat, Jul 9, 2016 at 4:37 AM, Alexey Brodkin
>>  wrote:
>> > 
>> > Hello,
>> > 
>> > I was playing with quite simple bridged setup on different boards
>> with > very recent kernels (4.6.3 as of this writing) and found one
>> interesting > behavior that I cannot yet understand and googling
>> din't help here as well.
>> > 
>> > My setup is pretty simple: >
>> -   --   -
>> > > 
>> > > HOST  |   | "Dumb AP"  |   | Wireless
>> client   | > > with DHCP |<->(eth0) (wlan0)<->|
>> attempting to | > > server|   |\ br0
>> / |   | get settings via DHCP | >
>> -   --   -
>> > 
>> > * HOST is my laptop with DHCP server that works for sure.  > *
>> "Dumb AP" is a separate board (I tried ARM-based Wandboard and
>> ARC-based >   AXS10x boards but results are exactly the same) with
>> wired (eth0) and wireless >   (wlan0) network controllers bridged
>> together (br0). That "br0" bridge flawlessly >   gets its settings
>> from DHCP server on host.  > * Wireless client could be either a
>> smatrphone or another laptop etc but >   what's important it should
>> be configured to get network settings by DHCP as well.
>> > 
>> > So what happens "br0" always gets network settings from DHCP server
>> on HOST.  > That's fine. But wireless client only reliably gets
>> settings from DHCP server > if IPv6 is enabled on "Dumb AP" board. If
>> IPv6 is disabled I may see that > wireless client sends "DHCP
>> Discover" then server replies with "DHCP Offer" but > that offer
>> never reaches wireless client.
>> 
>> 
>> Do you have WDS enabled? If not, DHCP has issues in that scenario:
>> https://wiki.openwrt.org/doc/howto/clientmode

If the Dumb AP's wireless interface is in ap-mode, then this shouldn't
be an issue.  It's only client-mode interfaces that have trouble with bridging.

I'd suggest running tcpdump on the Dumb AP's wireless interface and the
client's wireless interface and see which of them sees the various parts
of the DHCP handshake.


-- 
Russell Senior, President
russ...@personaltelco.net

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

2016-07-10 Thread Russell Senior

> "Alexey" == Alexey Brodkin  writes:

Alexey> Hi Aaron,
Alexey> On Sat, 2016-07-09 at 07:47 -0400, Aaron Z wrote:
>> On Sat, Jul 9, 2016 at 4:37 AM, Alexey Brodkin
>>  wrote:
>> > 
>> > Hello,
>> > 
>> > I was playing with quite simple bridged setup on different boards
>> with > very recent kernels (4.6.3 as of this writing) and found one
>> interesting > behavior that I cannot yet understand and googling
>> din't help here as well.
>> > 
>> > My setup is pretty simple: >
>> -   --   -
>> > > 
>> > > HOST  |   | "Dumb AP"  |   | Wireless
>> client   | > > with DHCP |<->(eth0) (wlan0)<->|
>> attempting to | > > server|   |\ br0
>> / |   | get settings via DHCP | >
>> -   --   -
>> > 
>> > * HOST is my laptop with DHCP server that works for sure.  > *
>> "Dumb AP" is a separate board (I tried ARM-based Wandboard and
>> ARC-based >   AXS10x boards but results are exactly the same) with
>> wired (eth0) and wireless >   (wlan0) network controllers bridged
>> together (br0). That "br0" bridge flawlessly >   gets its settings
>> from DHCP server on host.  > * Wireless client could be either a
>> smatrphone or another laptop etc but >   what's important it should
>> be configured to get network settings by DHCP as well.
>> > 
>> > So what happens "br0" always gets network settings from DHCP server
>> on HOST.  > That's fine. But wireless client only reliably gets
>> settings from DHCP server > if IPv6 is enabled on "Dumb AP" board. If
>> IPv6 is disabled I may see that > wireless client sends "DHCP
>> Discover" then server replies with "DHCP Offer" but > that offer
>> never reaches wireless client.
>> 
>> 
>> Do you have WDS enabled? If not, DHCP has issues in that scenario:
>> https://wiki.openwrt.org/doc/howto/clientmode

If the Dumb AP's wireless interface is in ap-mode, then this shouldn't
be an issue.  It's only client-mode interfaces that have trouble with bridging.

I'd suggest running tcpdump on the Dumb AP's wireless interface and the
client's wireless interface and see which of them sees the various parts
of the DHCP handshake.


-- 
Russell Senior, President
russ...@personaltelco.net

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

2016-07-09 Thread Alexey Brodkin

Hi Aaron,

On Sat, 2016-07-09 at 07:47 -0400, Aaron Z wrote:
> On Sat, Jul 9, 2016 at 4:37 AM, Alexey Brodkin
>  wrote:
> > 
> > Hello,
> > 
> > I was playing with quite simple bridged setup on different boards with
> > very recent kernels (4.6.3 as of this writing) and found one interesting
> > behavior that I cannot yet understand and googling din't help here as well.
> > 
> > My setup is pretty simple:
> > -   --   -
> > > 
> > > HOST  |   | "Dumb AP"  |   | Wireless client   |
> > > with DHCP |<->(eth0) (wlan0)<->| attempting to |
> > > server|   |\ br0 / |   | get settings via DHCP |
> > -   --   -
> > 
> > * HOST is my laptop with DHCP server that works for sure.
> > * "Dumb AP" is a separate board (I tried ARM-based Wandboard and ARC-based
> >   AXS10x boards but results are exactly the same) with wired (eth0) and 
> > wireless
> >   (wlan0) network controllers bridged together (br0). That "br0" bridge 
> > flawlessly
> >   gets its settings from DHCP server on host.
> > * Wireless client could be either a smatrphone or another laptop etc but
> >   what's important it should be configured to get network settings by DHCP 
> > as well.
> > 
> > So what happens "br0" always gets network settings from DHCP server on HOST.
> > That's fine. But wireless client only reliably gets settings from DHCP 
> > server
> > if IPv6 is enabled on "Dumb AP" board. If IPv6 is disabled I may see that
> > wireless client sends "DHCP Discover" then server replies with "DHCP Offer" 
> > but
> > that offer never reaches wireless client.
> 
>
> Do you have WDS enabled? If not, DHCP has issues in that scenario:
> https://wiki.openwrt.org/doc/howto/clientmode

I don't have WDS enabled. I tried to have as simple setup as possible.
Still from what I see in the Wiki article above problem happens when
there're 4 devices in the chain, right? Because as it says:
>8
The 802.11 standard only uses three MAC addresses for frames transmitted between
the Access Point and the Station. Frames transmitted from the Station to the AP
don't include the ethernet source MAC of the requesting host and response frames
are missing the destination ethernet MAC to address the target host behind the
client bridge.
>8

But in my case I only have 3 devices in the chain so I would think it's
something else but issue described in the article.

Anyways thanks for the hint.

-Alexey

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

2016-07-09 Thread Alexey Brodkin

Hi Aaron,

On Sat, 2016-07-09 at 07:47 -0400, Aaron Z wrote:
> On Sat, Jul 9, 2016 at 4:37 AM, Alexey Brodkin
>  wrote:
> > 
> > Hello,
> > 
> > I was playing with quite simple bridged setup on different boards with
> > very recent kernels (4.6.3 as of this writing) and found one interesting
> > behavior that I cannot yet understand and googling din't help here as well.
> > 
> > My setup is pretty simple:
> > -   --   -
> > > 
> > > HOST  |   | "Dumb AP"  |   | Wireless client   |
> > > with DHCP |<->(eth0) (wlan0)<->| attempting to |
> > > server|   |\ br0 / |   | get settings via DHCP |
> > -   --   -
> > 
> > * HOST is my laptop with DHCP server that works for sure.
> > * "Dumb AP" is a separate board (I tried ARM-based Wandboard and ARC-based
> >   AXS10x boards but results are exactly the same) with wired (eth0) and 
> > wireless
> >   (wlan0) network controllers bridged together (br0). That "br0" bridge 
> > flawlessly
> >   gets its settings from DHCP server on host.
> > * Wireless client could be either a smatrphone or another laptop etc but
> >   what's important it should be configured to get network settings by DHCP 
> > as well.
> > 
> > So what happens "br0" always gets network settings from DHCP server on HOST.
> > That's fine. But wireless client only reliably gets settings from DHCP 
> > server
> > if IPv6 is enabled on "Dumb AP" board. If IPv6 is disabled I may see that
> > wireless client sends "DHCP Discover" then server replies with "DHCP Offer" 
> > but
> > that offer never reaches wireless client.
> 
>
> Do you have WDS enabled? If not, DHCP has issues in that scenario:
> https://wiki.openwrt.org/doc/howto/clientmode

I don't have WDS enabled. I tried to have as simple setup as possible.
Still from what I see in the Wiki article above problem happens when
there're 4 devices in the chain, right? Because as it says:
>8
The 802.11 standard only uses three MAC addresses for frames transmitted between
the Access Point and the Station. Frames transmitted from the Station to the AP
don't include the ethernet source MAC of the requesting host and response frames
are missing the destination ethernet MAC to address the target host behind the
client bridge.
>8

But in my case I only have 3 devices in the chain so I would think it's
something else but issue described in the article.

Anyways thanks for the hint.

-Alexey

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

2016-07-09 Thread Aaron Z

On Sat, Jul 9, 2016 at 4:37 AM, Alexey Brodkin
 wrote:
> Hello,
>
> I was playing with quite simple bridged setup on different boards with
> very recent kernels (4.6.3 as of this writing) and found one interesting
> behavior that I cannot yet understand and googling din't help here as well.
>
> My setup is pretty simple:
> -   --   -
> | HOST  |   | "Dumb AP"  |   | Wireless client   |
> | with DHCP |<->(eth0) (wlan0)<->| attempting to |
> | server|   |\ br0 / |   | get settings via DHCP |
> -   --   -
>
> * HOST is my laptop with DHCP server that works for sure.
> * "Dumb AP" is a separate board (I tried ARM-based Wandboard and ARC-based
>   AXS10x boards but results are exactly the same) with wired (eth0) and 
> wireless
>   (wlan0) network controllers bridged together (br0). That "br0" bridge 
> flawlessly
>   gets its settings from DHCP server on host.
> * Wireless client could be either a smatrphone or another laptop etc but
>   what's important it should be configured to get network settings by DHCP as 
> well.
>
> So what happens "br0" always gets network settings from DHCP server on HOST.
> That's fine. But wireless client only reliably gets settings from DHCP server
> if IPv6 is enabled on "Dumb AP" board. If IPv6 is disabled I may see that
> wireless client sends "DHCP Discover" then server replies with "DHCP Offer" 
> but
> that offer never reaches wireless client.
Do you have WDS enabled? If not, DHCP has issues in that scenario:
https://wiki.openwrt.org/doc/howto/clientmode

Aaron Z

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

2016-07-09 Thread Aaron Z

On Sat, Jul 9, 2016 at 4:37 AM, Alexey Brodkin
 wrote:
> Hello,
>
> I was playing with quite simple bridged setup on different boards with
> very recent kernels (4.6.3 as of this writing) and found one interesting
> behavior that I cannot yet understand and googling din't help here as well.
>
> My setup is pretty simple:
> -   --   -
> | HOST  |   | "Dumb AP"  |   | Wireless client   |
> | with DHCP |<->(eth0) (wlan0)<->| attempting to |
> | server|   |\ br0 / |   | get settings via DHCP |
> -   --   -
>
> * HOST is my laptop with DHCP server that works for sure.
> * "Dumb AP" is a separate board (I tried ARM-based Wandboard and ARC-based
>   AXS10x boards but results are exactly the same) with wired (eth0) and 
> wireless
>   (wlan0) network controllers bridged together (br0). That "br0" bridge 
> flawlessly
>   gets its settings from DHCP server on host.
> * Wireless client could be either a smatrphone or another laptop etc but
>   what's important it should be configured to get network settings by DHCP as 
> well.
>
> So what happens "br0" always gets network settings from DHCP server on HOST.
> That's fine. But wireless client only reliably gets settings from DHCP server
> if IPv6 is enabled on "Dumb AP" board. If IPv6 is disabled I may see that
> wireless client sends "DHCP Discover" then server replies with "DHCP Offer" 
> but
> that offer never reaches wireless client.
Do you have WDS enabled? If not, DHCP has issues in that scenario:
https://wiki.openwrt.org/doc/howto/clientmode

Aaron Z

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

Re: [LEDE-DEV] DHCP via bridge in case of IPv4

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