[gentoo-user] What happened to my 2nd eth0?

[gentoo-user] What happened to my 2nd eth0?

[Walter Dnes]

  My DSL router modem is at 192.168.123.254.  I have an HDHomerun
network TV tuner that insists on coming up somewhere in the 169.254.X.Y
block.  Up until upgrading from 32 to 64 bits, I was able to see a 2nd
eth0 (i.e. eth0:1) using the following /etc/conf.d/net setup...

config_eth0="
192.168.123.251/29 broadcast 192.168.123.255
169.254.1.1/16 broadcast 169.254.255.255"
routes_eth0="
default via 192.168.123.254 metric 20
192.168.123.248/29 via 192.168.123.254 metric 0
169.254.0.0/16 via 169.254.1.1 metric 0"

  The 2nd interface is no longer being set up.  As amatter of fact, it
appears to be totally unavailable.  E.g....

[d531][root][~] /etc/init.d/net.eth0 stop
 * Unmounting network filesystems ...                                     [ ok ]
 * Bringing down interface eth0
[d531][root][~] ifconfig eth0:0 192.168.123.251/29 broadcast 192.168.123.255
SIOCSIFNETMASK: Cannot assign requested address
[d531][root][~] ifconfig eth0 192.168.123.251/29 broadcast 192.168.123.255
[d531][root][~]

  So my system doesn't support even the concept of an alias for eth0.
Looking at the ifconfig manpage...

interface
       The  name  of the interface.  This is usually a driver name fol-
       lowed by a unit number, for example eth0 for the first  Ethernet
       interface.  If  your  kernel  supports alias interfaces, you can
       specify them with eth0:0 for the first alias of  eth0.  You  can
       use  them  to assign a second address. To delete an alias inter-
       face use ifconfig eth0:0 down.  Note: for every scope (i.e. same
       net  with  address/netmask combination) all aliases are deleted,
       if you delete the first (primary).

  I see "If  your  kernel  supports alias interfaces".  During the
upgrade, I built the kernel from square 1.  I already ran into problems
with not enabling FUSE in the new kernel, which killed MTP until I
enabled it.  I wouldn't be surprised if I've disabled some kernel
parameter which is required to enable interface aliases.  I didn't see
anything obvious in "make menuconfig".  A Google search turned up a
gazillion examples of "how to create an alias using ifconfig".  That's
not what I want.  I want the kernel setting that allows creating alias
interfaces.

-- 
Walter Dnes <waltdnes@waltdnes.org>
I don't run "desktop environments"; I run useful applications

Re: [gentoo-user] What happened to my 2nd eth0?

[Mick]

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On Sunday 22 Feb 2015 04:52:34 Walter Dnes wrote:
>   My DSL router modem is at 192.168.123.254.  I have an HDHomerun
> network TV tuner that insists on coming up somewhere in the 169.254.X.Y
> block.  Up until upgrading from 32 to 64 bits, I was able to see a 2nd
> eth0 (i.e. eth0:1) using the following /etc/conf.d/net setup...
> 
> config_eth0="
> 192.168.123.251/29 broadcast 192.168.123.255
> 169.254.1.1/16 broadcast 169.254.255.255"

Is there a reason you need to define a broadcast if you are using CIDR 
notation?


> routes_eth0="
> default via 192.168.123.254 metric 20
> 192.168.123.248/29 via 192.168.123.254 metric 0

Isn't the above redundant if you have defined an identical default route?

> 169.254.0.0/16 via 169.254.1.1 metric 0"



>   The 2nd interface is no longer being set up.  As amatter of fact, it
> appears to be totally unavailable.  E.g....
> 
> [d531][root][~] /etc/init.d/net.eth0 stop
>  * Unmounting network filesystems ...                                     [
> ok ] * Bringing down interface eth0
> [d531][root][~] ifconfig eth0:0 192.168.123.251/29 broadcast
> 192.168.123.255 SIOCSIFNETMASK: Cannot assign requested address
> [d531][root][~] ifconfig eth0 192.168.123.251/29 broadcast 192.168.123.255
> [d531][root][~]
> 
>   So my system doesn't support even the concept of an alias for eth0.
> Looking at the ifconfig manpage...

Unless you have set up:

modules="!iproute2"

netifrc will not use ifconfig.

> interface
>        The  name  of the interface.  This is usually a driver name fol-
>        lowed by a unit number, for example eth0 for the first  Ethernet
>        interface.  If  your  kernel  supports alias interfaces, you can
>        specify them with eth0:0 for the first alias of  eth0.  You  can
>        use  them  to assign a second address. To delete an alias inter-
>        face use ifconfig eth0:0 down.  Note: for every scope (i.e. same
>        net  with  address/netmask combination) all aliases are deleted,
>        if you delete the first (primary).
> 
>   I see "If  your  kernel  supports alias interfaces".  During the
> upgrade, I built the kernel from square 1.  I already ran into problems
> with not enabling FUSE in the new kernel, which killed MTP until I
> enabled it.  I wouldn't be surprised if I've disabled some kernel
> parameter which is required to enable interface aliases.  I didn't see
> anything obvious in "make menuconfig".  A Google search turned up a
> gazillion examples of "how to create an alias using ifconfig".  That's
> not what I want.  I want the kernel setting that allows creating alias
> interfaces.

The kernel option you want is:

CONFIG_IP_MULTIPLE_TABLES=y


Also, if you want to set up the HDHomerun to do the right thing, i.e. NOT use 
local-link addresses, then according to Google you could try:

“A static IP address can be configured using the following command (the quotes 
are required as shown):
Format:  hdhomerun_config <old ip> set /sys/ipaddr "<new ip> <subnet> 
<gateway>"
Example: hdhomerun_config 169.254.34.98 set /sys/ipaddr "10.10.20.43 
255.255.255.0 10.10.20.1"

The TECH3 can be configured for DHCP operation (default) using the following 
command:
Format:  hdhomerun_config <old ip> set /sys/ipaddr dhcp
Example: hdhomerun_config 169.254.34.98 set /sys/ipaddr dhcp”


I think different variables can be saved in its /sys/boot, including a static 
IP address, so that they persist over reboots.

HTH
-- 
Regards,
Mick

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[gentoo-user] Re: [SOLVED] What happened to my 2nd eth0?

[Walter Dnes]

On Sun, Feb 22, 2015 at 09:01:47AM +0000, Mick wrote
> On Sunday 22 Feb 2015 04:52:34 Walter Dnes wrote:
> >   My DSL router modem is at 192.168.123.254.  I have an HDHomerun
> > network TV tuner that insists on coming up somewhere in the 169.254.X.Y
> > block.  Up until upgrading from 32 to 64 bits, I was able to see a 2nd
> > eth0 (i.e. eth0:1) using the following /etc/conf.d/net setup...
> > 
> > config_eth0="
> > 192.168.123.251/29 broadcast 192.168.123.255
> > 169.254.1.1/16 broadcast 169.254.255.255"
> 
> Is there a reason you need to define a broadcast if you are using CIDR 
> notation?

  I've always done it that way.  At one time I had a router that could
be made to send logs to a specified IP address.  By setting their
broadcast addresses to 192.168.123.255, and having the router log to
that address, I could make both of my machines pick up the remote logs
from the router.

> > routes_eth0="
> > default via 192.168.123.254 metric 20
> > 192.168.123.248/29 via 192.168.123.254 metric 0
> 
> Isn't the above redundant if you have defined an identical default route?
> 
> > 169.254.0.0/16 via 169.254.1.1 metric 0"

  Another item that stopped working a while ago...

  I have a dialup connection for emergency backup use.  Before the
format of the /etc/conf.d/net file changed, I could simultaneously...

* have eth0 as default route with "expensive metric" 20
* have ppp0 take over when dialup is active, with a "cheaper metric"
* still be able to have my 2 machines talk to each other over eth0, even
  while the dialup connection ppp0 is active
* have eth0 take over again as default route when ppp0 drops

> Unless you have set up:
> 
> modules="!iproute2"
> 
> netifrc will not use ifconfig.

  I've noticed iproute2 showing up recently in emerge.  ***YES IT
WORKS***.  Thank you very much.  I am now getting OTA TV to my desktop
again.  Slight modification.  Using that search string in Google, I
found http://www.michaeldolan.com/Tutorials/Downloads/conf.d/net

  My revised /etc/conf.d/net script is

modules=( "!iproute2" )
config_eth0="
192.168.123.251/29 broadcast 192.168.123.255
169.254.1.1/16 broadcast 169.254.255.255"
routes_eth0="
default via 192.168.123.254 metric 20
192.168.123.248/29 via 192.168.123.254 metric 0
169.254.0.0/16 via 169.254.1.1 metric 0"

edit... I finally found the documentation (see below).  I still have to
fix up the "metric" and "broadcast" parameters.  For now, I'm happy to
have the TV signal coming to my desktop.

...and "ifconfig" returns...

eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.123.251  netmask 255.255.255.248  broadcast 192.168.123.255
        ether 00:1d:09:96:6c:1c  txqueuelen 1000  (Ethernet)
        RX packets 1049019  bytes 1501104544 (1.3 GiB)
        RX errors 0  dropped 5  overruns 0  frame 0
        TX packets 569447  bytes 45295143 (43.1 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0
        device interrupt 20  memory 0xfdfc0000-fdfe0000  

eth0:1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 169.254.1.1  netmask 255.255.0.0  broadcast 169.254.255.255
        ether 00:1d:09:96:6c:1c  txqueuelen 1000  (Ethernet)
        device interrupt 20  memory 0xfdfc0000-fdfe0000  

lo: flags=73<UP,LOOPBACK,RUNNING>  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        loop  txqueuelen 0  (Local Loopback)
        RX packets 8  bytes 480 (480.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 8  bytes 480 (480.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

  I would have appreciated a news item telling me that /etc/conf.d/net
was going to change default behaviour, before it happened and caused
breakage on my system.  Or did it happen, and I missed it?

> CONFIG_IP_MULTIPLE_TABLES=y

  I do not have that option available it in my current kernel, or in the
backup from before I switched from 32-bit to 64-bit mode.  Not that it
matters, now that I have things working.


  Given that iproute2 is now the default, I assume that ifconfig will be
dropped sometime down the road.  Documentation "could be better".  At
the top of /etc/conf.d/net I see...
# This blank configuration will automatically use DHCP for any net.*
# scripts in /etc/init.d.  To create a more complete configuration,
# please review /etc/conf.d/net.example and save your configuration
# in /etc/conf.d/net (this file :]!).

# Actually /usr/share/doc/openrc-<version>/net.example is where to look
# for example setup.

  Guess what... neither of those example files exist.  It's actually
/usr/share/doc/netifrc-<version>/net.example.bz2 (Where would I be
without Google?)  Also using Google, I found
http://www.policyrouting.org/iproute2.doc.html which is quite complex.
Looks like it's time to play around with the "ip" command and try to
duplicate my current setup.  Does anyone have a multi-route setup
similar to mine configured with iproute2?  The net.example file says

# If you need more than one address, you can use something like this
# NOTE: ifconfig creates an aliased device for each extra IPv4 address
#       (eth0:1, eth0:2, etc)
#       iproute2 does not do this as there is no need to
# WARNING: You cannot mix multiple addresses on a line with other parameters!
#config_eth0="192.168.0.2/24 192.168.0.3/24 192.168.0.4/24"
# However, that only works with CIDR addresses, so you can't use
# netmask.

  What exactly do they mean by...
"iproute2 does not do this as there is no need to"

-- 
Walter Dnes <waltdnes@waltdnes.org>
I don't run "desktop environments"; I run useful applications

Re: [gentoo-user] Re: [SOLVED] What happened to my 2nd eth0?

[Mick]

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On Monday 23 Feb 2015 08:39:42 Walter Dnes wrote:

> Looks like it's time to play around with the "ip" command and try to
> duplicate my current setup.  Does anyone have a multi-route setup
> similar to mine configured with iproute2?  The net.example file says
> 
> # If you need more than one address, you can use something like this
> # NOTE: ifconfig creates an aliased device for each extra IPv4 address
> #       (eth0:1, eth0:2, etc)
> #       iproute2 does not do this as there is no need to
> # WARNING: You cannot mix multiple addresses on a line with other
> parameters! #config_eth0="192.168.0.2/24 192.168.0.3/24 192.168.0.4/24"
> # However, that only works with CIDR addresses, so you can't use
> # netmask.
> 
>   What exactly do they mean by...
> "iproute2 does not do this as there is no need to"

There is no need to create virtual interfaces like eth0:1 to be able to have 
secondary IP addresses.  The ip command adds them to the same eth0 interface.

When I use VPN I can see that my interface has a secondary LAN address created 
by VPN, but it does not have an additional virtual NIC.

The only thing is that if my primary IP address goes down temporarily, the 
secondary address becomes primary and stays there.  I need to look at the VPN 
configuration to see how to define the VPN LAN as a secondary subnet, but this 
is not related to your question.

PS.  Did you look at setting your desired subnet rather than a local-link 
auto-configured address at your HDHomerun device?

-- 
Regards,
Mick

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Re: [gentoo-user] Re: [SOLVED] What happened to my 2nd eth0?

[Walter Dnes]

On Tue, Feb 24, 2015 at 06:43:19AM +0000, Mick wrote

> PS.  Did you look at setting your desired subnet rather than a local-link 
> auto-configured address at your HDHomerun device?

  Not yet.  I'm still cleaning up some odds-n-ends of my "simple upgrade"
from 32-bit to 64-bit mode.  Also, as a matter of principle, I'd like to
learn how to set up multiple routes using the iproute2 suite.  This
looks like a perfect "learning opportunity".

-- 
Walter Dnes <waltdnes@waltdnes.org>
I don't run "desktop environments"; I run useful applications

Re: [gentoo-user] Re: [SOLVED] What happened to my 2nd eth0?

[Tom H]

On Tue, Feb 24, 2015 at 1:43 AM, Mick <michaelkintzios@gmail.com> wrote:
> On Monday 23 Feb 2015 08:39:42 Walter Dnes wrote:
>>
>> Looks like it's time to play around with the "ip" command and try to
>> duplicate my current setup.  Does anyone have a multi-route setup
>> similar to mine configured with iproute2?  The net.example file says
>>
>> # If you need more than one address, you can use something like this
>> # NOTE: ifconfig creates an aliased device for each extra IPv4 address
>> #       (eth0:1, eth0:2, etc)
>> #       iproute2 does not do this as there is no need to
>> # WARNING: You cannot mix multiple addresses on a line with other
>> parameters! #config_eth0="192.168.0.2/24 192.168.0.3/24 192.168.0.4/24"
>> # However, that only works with CIDR addresses, so you can't use
>> # netmask.
>>
>>   What exactly do they mean by...
>> "iproute2 does not do this as there is no need to"
>
> There is no need to create virtual interfaces like eth0:1 to be able to have
> secondary IP addresses.  The ip command adds them to the same eth0 interface.

Labels (iproute2 aliases) aren't required but can be useful:

# ip a sh dev wlan0
2: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP
group default qlen 1000
    link/ether e8:2a:ea:0f:68:ec brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.240/24 brd 192.168.1.255 scope global wlan0
       valid_lft forever preferred_lft forever

# ip a add 192.168.1.250/24 brd + label wlan0:0 dev wlan0

# ip a sh dev wlan0
2: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP
group default qlen 1000
    link/ether e8:2a:ea:0f:68:ec brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.240/24 brd 192.168.1.255 scope global wlan0
       valid_lft forever preferred_lft forever
    inet 192.168.1.250/24 brd 192.168.1.255 scope global secondary wlan0:0
       valid_lft forever preferred_lft forever

# ip a sh label wlan0:0
    inet 192.168.1.250/24 brd 192.168.1.255 scope global secondary wlan0:0
       valid_lft forever preferred_lft forever

# ip a fl label wlan0:0

# ip a sh dev wlan0
2: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP
group default qlen 1000
    link/ether e8:2a:ea:0f:68:ec brd ff:ff:ff:ff:ff:ff
    inet 192.168.1.240/24 brd 192.168.1.255 scope global wlan0
       valid_lft forever preferred_lft forever

Re: [gentoo-user] Re: [SOLVED] What happened to my 2nd eth0?

[Walter Dnes]

On Tue, Feb 24, 2015 at 05:08:50PM -0500, Tom H wrote

> # ip a sh dev wlan0
> 2: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP
> group default qlen 1000
>     link/ether e8:2a:ea:0f:68:ec brd ff:ff:ff:ff:ff:ff
>     inet 192.168.1.240/24 brd 192.168.1.255 scope global wlan0
>        valid_lft forever preferred_lft forever
>     inet 192.168.1.250/24 brd 192.168.1.255 scope global secondary wlan0:0
>        valid_lft forever preferred_lft forever

  I've been Googling and playing around a bit.  I have the main ADSL
connection to the world working via iproute2, but not the 169.254.0.0/16
net.  I can't figure out what I'm doing wrong.  My setup...

* desktop PC 192.168.123.251/29, with NIC interface eth0
* HDHomerun network TV tuner in 169.254.0.0/16

  Both are attached to an ADSL router at 192.168.123.254   I start off
with "/etc/init.d/net.eth0 stop" to get to a known state.  Then I run a
script which issues the commands...

ip link set eth0 down
ip link set eth0 up
ip address add 192.168.123.251/29 dev eth0
ip route add default via 192.168.123.254 metric 100
ip address add 169.254.1.1/16 dev eth0
ip route add 169.254.0.0/16 via 192.168.123.254 metric 0
ip address show
ip route show

  The output from the commands is...
 
RTNETLINK answers: File exists
RTNETLINK answers: File exists
RTNETLINK answers: File exists
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 brd 127.255.255.255 scope host lo
       valid_lft forever preferred_lft forever
2: eth0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast state DOWN group default qlen 1000
    link/ether 00:1d:09:96:6c:1c brd ff:ff:ff:ff:ff:ff
    inet 192.168.123.251/29 scope global eth0
       valid_lft forever preferred_lft forever
    inet 169.254.1.1/16 scope global eth0
       valid_lft forever preferred_lft forever
default via 192.168.123.254 dev eth0  metric 100 
127.0.0.0/8 dev lo  scope host 
169.254.0.0/16 dev eth0  proto kernel  scope link  src 169.254.1.1 
192.168.123.248/29 dev eth0  proto kernel  scope link  src 192.168.123.251


  Like I said above, the default route to the world works, but not to
169.254.0.0.  Once I get that figured out, the next questions are...
1) What is the setup in /etc/conf.d/net to accomplish that?
2) Should iproute2 be built with or without the "iptables" flag?

-- 
Walter Dnes <waltdnes@waltdnes.org>
I don't run "desktop environments"; I run useful applications

Re: [gentoo-user] Re: [SOLVED] What happened to my 2nd eth0?

[Tom H]

On Thu, Feb 26, 2015 at 1:26 AM, Walter Dnes <waltdnes@waltdnes.org> wrote:
>
> I've been Googling and playing around a bit. I have the main ADSL
> connection to the world working via iproute2, but not the 169.254.0.0/16
> net. I can't figure out what I'm doing wrong.  My setup...
>
> * desktop PC 192.168.123.251/29, with NIC interface eth0
> * HDHomerun network TV tuner in 169.254.0.0/16
>
> Both are attached to an ADSL router at 192.168.123.254  I start off
> with "/etc/init.d/net.eth0 stop" to get to a known state. Then I run a
> script which issues the commands...
>
> ip link set eth0 down
> ip link set eth0 up
> ip address add 192.168.123.251/29 dev eth0
> ip route add default via 192.168.123.254 metric 100
> ip address add 169.254.1.1/16 dev eth0
> ip route add 169.254.0.0/16 via 192.168.123.254 metric 0
> ip address show
> ip route show
>
> The output from the commands is...
>
> RTNETLINK answers: File exists
> RTNETLINK answers: File exists

These two errors are due to the fact that "ip l set down dev eth0"
doesn't delete assigned ip addresses, only assigned routes.

So when you run "ip a add ...", you're setting addresses that are already set.


> RTNETLINK answers: File exists

This error is due to the fact that "ip a add 168.254.1.1/16 dev eth0"
includes an automatic "ip r add 169.254.0.0/16 src 169.254.1.1 proto
kernel scope link dev eth0" so there's already a route for
"169.254.0.0/16".

You could run "ip r del 168.254.0.0/16 dev eth0" and then "ip r add
169.254.0.0/16 via 192.168.123.254".


> 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default
>     link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
>     inet 127.0.0.1/8 brd 127.255.255.255 scope host lo
>        valid_lft forever preferred_lft forever
> 2: eth0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast state DOWN group default qlen 1000
>     link/ether 00:1d:09:96:6c:1c brd ff:ff:ff:ff:ff:ff
>     inet 192.168.123.251/29 scope global eth0
>        valid_lft forever preferred_lft forever
>     inet 169.254.1.1/16 scope global eth0
>        valid_lft forever preferred_lft forever
> default via 192.168.123.254 dev eth0  metric 100
> 127.0.0.0/8 dev lo  scope host
> 169.254.0.0/16 dev eth0  proto kernel  scope link  src 169.254.1.1
> 192.168.123.248/29 dev eth0  proto kernel  scope link  src 192.168.123.251
>
> Like I said above, the default route to the world works, but not to
> 169.254.0.0. Once I get that figured out, the next questions are...
> 1) What is the setup in /etc/conf.d/net to accomplish that?

You'd originally had

routes_eth0="
default via 192.168.123.254 metric 20
192.168.123.248/29 via 192.168.123.254 metric 0
169.254.0.0/16 via 169.254.1.1 metric 0"

so you'd have to change the last line.


> 2) Should iproute2 be built with or without the "iptables" flag?

There may be other use cases but the only one that I can think of is
that this flag allows you to use "iptables ... -j MARK --set-mark
walt" and then "ip ru add ... fwmark walt ...".

Re: [gentoo-user] Re: [SOLVED] What happened to my 2nd eth0?

[Walter Dnes]

  Let's forget about additional routes with different metrics, and try
to get the simplest case working, and move forward from there.  If I have
/etc/conf.d/net as...

modules=( "!iproute2" )
config_eth0="
192.168.123.251/29 broadcast 192.168.123.255
169.254.1.1/16 broadcast 169.254.255.255"
routes_eth0="
default via 192.168.123.254"

...and run "/etc/init.d/net.eth0 restart", I can access the device on
169.254.0.0/16.  If I comment out the "modules=( "!iproute2" )" line and
run "/etc/init.d/net.eth0 restart", I can't access the device.  The
above is the minimal "net" file require for ifconfig.  I want to be able
to work this down the road when ifconfig goes away, and iproute2 becomes
mandatory.

  I'm still trying to wrap my brain around how the ADSL router decides
whether to look for 169.254.0.0/16 on the ethernet cable to the TV tuner
rather than on the phone line going to my ISP, and then the world.

-- 
Walter Dnes <waltdnes@waltdnes.org>
I don't run "desktop environments"; I run useful applications

Re: [gentoo-user] Re: [SOLVED] What happened to my 2nd eth0?

[Tom H]

On Thu, Feb 26, 2015 at 1:57 PM, Walter Dnes <waltdnes@waltdnes.org> wrote:
>
> Let's forget about additional routes with different metrics, and try
> to get the simplest case working, and move forward from there. If I have
> /etc/conf.d/net as...
>
> modules=( "!iproute2" )
> config_eth0="
> 192.168.123.251/29 broadcast 192.168.123.255
> 169.254.1.1/16 broadcast 169.254.255.255"
> routes_eth0="
> default via 192.168.123.254"
>
> ...and run "/etc/init.d/net.eth0 restart", I can access the device on
> 169.254.0.0/16. If I comment out the "modules=( "!iproute2" )" line and
> run "/etc/init.d/net.eth0 restart", I can't access the device. The
> above is the minimal "net" file require for ifconfig. I want to be able
> to work this down the road when ifconfig goes away, and iproute2 becomes
> mandatory.

No idea.

I set up a test VM. I don't have a 169.254 device to try to access but
I have the same "ip a" and "ip r" output for the net-tools and
iproute2 setups (except for the "eth0:1" label in the net-tools
setup).


gentest conf.d # cat net
modules="!iproute2"
config_eth0="
10.0.2.15/24
169.254.1.1/16"
routes_eth0="default via 10.0.2.2"
dns_servers_eth0="8.8.8.8"


gentest conf.d # ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
group default
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 brd 127.255.255.255 scope host lo
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast
state UP group default qlen 1000
    link/ether 52:54:00:20:20:20 brd ff:ff:ff:ff:ff:ff
    inet 10.0.2.15/24 brd 10.0.2.255 scope global eth0
       valid_lft forever preferred_lft forever
    inet 169.254.1.1/16 brd 169.254.255.255 scope global eth0:1
       valid_lft forever preferred_lft forever


gentest conf.d # ip r
default via 10.0.2.2 dev eth0  metric 2
10.0.2.0/24 dev eth0  proto kernel  scope link  src 10.0.2.15
127.0.0.0/8 dev lo  scope host
169.254.0.0/16 dev eth0  proto kernel  scope link  src 169.254.1.1


gentest conf.d # vi net


gentest conf.d # cat net
config_eth0="
10.0.2.15/24
169.254.1.1/16"
routes_eth0="default via 10.0.2.2"
dns_servers_eth0="8.8.8.8"


gentest conf.d # rc-service net.eth0 restart


gentest conf.d # ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
group default
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 brd 127.255.255.255 scope host lo
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast
state UP group default qlen 1000
    link/ether 52:54:00:20:20:20 brd ff:ff:ff:ff:ff:ff
    inet 10.0.2.15/24 brd 10.0.2.255 scope global eth0
       valid_lft forever preferred_lft forever
    inet 169.254.1.1/16 brd 169.254.255.255 scope global eth0
       valid_lft forever preferred_lft forever


gentest conf.d # ip r
default via 10.0.2.2 dev eth0  metric 2
10.0.2.0/24 dev eth0  proto kernel  scope link  src 10.0.2.15
127.0.0.0/8 dev lo  scope host
169.254.0.0/16 dev eth0  proto kernel  scope link  src 169.254.1.1




> I'm still trying to wrap my brain around how the ADSL router decides
> whether to look for 169.254.0.0/16 on the ethernet cable to the TV tuner
> rather than on the phone line going to my ISP, and then the world.

169.254 isn't supposed to be routable so the router might be set up
not to route it out to the world.

You'd be better off setting up a 192.168 address on the tuner, if possible.

Re: [gentoo-user] Re: [SOLVED] What happened to my 2nd eth0?

[Walter Dnes]

On Thu, Feb 26, 2015 at 05:59:26PM -0500, Tom H wrote
> 
> 169.254 isn't supposed to be routable so the router might be set up
> not to route it out to the world.
> 
> You'd be better off setting up a 192.168 address on the tuner, if possible.

But if I include the line...

modules="!iproute2"

...it works perfectly.  What's frustrating is that it works under
ifconfig, but not under iproute2.  I'll check with the local linux user
group in town (mailing list) to see if I can get any hints.

-- 
Walter Dnes <waltdnes@waltdnes.org>
I don't run "desktop environments"; I run useful applications

[gentoo-user] Why my wierd ifconfig setup won't work in iproute2... ever.

[Walter Dnes]

On Thu, Feb 26, 2015 at 11:27:56PM -0500, Walter Dnes wrote
> 
> But if I include the line...
> 
> modules="!iproute2"
> 
> ...it works perfectly.  What's frustrating is that it works under
> ifconfig, but not under iproute2.  I'll check with the local linux
> user group in town (mailing list) to see if I can get any hints.

  I now have the answer.  It's not what I wanted to hear, but at least I
can stop pounding my head against a brick wall.  I found out from the
networking gurus on the local Linux mailing list that...

* ifconfig is ancient (goes back to before 2005)

* back then 169.254.0.0/16 was just another address block, and ifconfig
  happily treats it as such

* in May 2005, RFC3927 was done http://www.ietf.org/rfc/rfc3927.txt
  It defined IPV4 link-local networking in 169.254.0.0/16

* it says, amongst other things...
> This document does not recommend that IPv4 Link-Local addresses and
> routable addresses be configured simultaneously on the same interface.

* iproute2 is relatively new, and follows that recommendation.  It's
  probably hard-coded not to support link-local and non-link-local
  addresses simultaneously on the same NIC.

* My only option in an iproute2-only environment would be to get a 2nd
  NIC and attach the TV tuner to it.

* My HDHomerun tuner is almost a museum-piece (spring of 2010).  I
  figure that by the time ifconfig support is finally deprecated, I'll
  be looking for a new tuner, rather than buying another NIC.

  So I'll keep going with 'modules="!iproute2"' until ifconfig is
deprecated.

-- 
Walter Dnes <waltdnes@waltdnes.org>
I don't run "desktop environments"; I run useful applications

Re: [gentoo-user] Why my wierd ifconfig setup won't work in iproute2... ever.

[Mick]

[-- Attachment #1: Type: Text/Plain, Size: 2017 bytes --]

On Sunday 01 Mar 2015 03:22:03 Walter Dnes wrote:
> On Thu, Feb 26, 2015 at 11:27:56PM -0500, Walter Dnes wrote
> 
> > But if I include the line...
> > 
> > modules="!iproute2"
> > 
> > ...it works perfectly.  What's frustrating is that it works under
> > ifconfig, but not under iproute2.  I'll check with the local linux
> > user group in town (mailing list) to see if I can get any hints.
> 
>   I now have the answer.  It's not what I wanted to hear, but at least I
> can stop pounding my head against a brick wall.  I found out from the
> networking gurus on the local Linux mailing list that...
> 
> * ifconfig is ancient (goes back to before 2005)
> 
> * back then 169.254.0.0/16 was just another address block, and ifconfig
>   happily treats it as such
> 
> * in May 2005, RFC3927 was done http://www.ietf.org/rfc/rfc3927.txt
>   It defined IPV4 link-local networking in 169.254.0.0/16
> 
> * it says, amongst other things...
> 
> > This document does not recommend that IPv4 Link-Local addresses and
> > routable addresses be configured simultaneously on the same interface.
> 
> * iproute2 is relatively new, and follows that recommendation.  It's
>   probably hard-coded not to support link-local and non-link-local
>   addresses simultaneously on the same NIC.
> 
> * My only option in an iproute2-only environment would be to get a 2nd
>   NIC and attach the TV tuner to it.
> 
> * My HDHomerun tuner is almost a museum-piece (spring of 2010).  I
>   figure that by the time ifconfig support is finally deprecated, I'll
>   be looking for a new tuner, rather than buying another NIC.
> 
>   So I'll keep going with 'modules="!iproute2"' until ifconfig is
> deprecated.

Out of interest, you didn't say if you tried adding manually a route in your 
/etc/conf.d/net for the link-local address space to see if it works:

routes_eth0="
default via 192.168.123.254
169.254.0.0/16 via 169.254.1.1"  <==Add this route for 169.254.0.0/16==

-- 
Regards,
Mick

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Re: [gentoo-user] Why my wierd ifconfig setup won't work in iproute2... ever.

[Walter Dnes]

On Sun, Mar 01, 2015 at 09:12:07AM +0000, Mick wrote
> 
> Out of interest, you didn't say if you tried adding manually a route
> in your /etc/conf.d/net for the link-local address space to see if
> it works:
> 
> routes_eth0="
> default via 192.168.123.254
> 169.254.0.0/16 via 169.254.1.1"  <==Add this route for 169.254.0.0/16==

  That's *EXACTLY* what I was doing originally.  See my post from
February 21st where I started this thread

config_eth0="
192.168.123.251/29 broadcast 192.168.123.255
169.254.1.1/16 broadcast 169.254.255.255"
routes_eth0="
default via 192.168.123.254 metric 20
192.168.123.248/29 via 192.168.123.254 metric 0
169.254.0.0/16 via 169.254.1.1 metric 0"

  Note that the "redundant route" is to allow my PC to talk to other
machines on my little LAN when using a dialup connection as emergency
backup.

* It worked under ifconfig before iproute2 showed up

* It stopped working when iproute2 became the default

* It started working again when I turned off iproute2 with the line
  modules=( "!iproute2" )

  Like I said in my original message, it worked under ifconfig, but
failed under iproute2.

-- 
Walter Dnes <waltdnes@waltdnes.org>
I don't run "desktop environments"; I run useful applications

Re: [gentoo-user] Why my wierd ifconfig setup won't work in iproute2... ever.

[Walter Dnes]

On Sat, Feb 28, 2015 at 10:22:03PM -0500, Walter Dnes wrote

> * My HDHomerun tuner is almost a museum-piece (spring of 2010).  I
>   figure that by the time ifconfig support is finally deprecated, I'll
>   be looking for a new tuner, rather than buying another NIC.

  See https://www.youtube.com/watch?v=JXmi-6nVhCM which is the exact
same model I have.  I bought mine in 2010, but the reviewer notes that
it won some award at CES2008.  Consider it a 2008, possibly 2007, model.

-- 
Walter Dnes <waltdnes@waltdnes.org>
I don't run "desktop environments"; I run useful applications

Re: [gentoo-user] Why my wierd ifconfig setup won't work in iproute2... ever.

[Daniel Frey]

On 02/28/2015 07:22 PM, Walter Dnes wrote:
>> This document does not recommend that IPv4 Link-Local addresses and
>> routable addresses be configured simultaneously on the same interface.
> 
> * My only option in an iproute2-only environment would be to get a 2nd
>   NIC and attach the TV tuner to it.
> 
> * My HDHomerun tuner is almost a museum-piece (spring of 2010).  I
>   figure that by the time ifconfig support is finally deprecated, I'll
>   be looking for a new tuner, rather than buying another NIC.
> 
>   So I'll keep going with 'modules="!iproute2"' until ifconfig is
> deprecated.
> 

I got my HDHomerun tuner around then too, but I decided back then
(without reading the manual) that I didn't want it on my "main" NIC, so
I bought an Intel pci-e NIC and dedicated the Homerun to it.

Every once in a while I move the computer (unplugging everything) and
when I go to plug it back in I can never remember which network port is
which. I should really label those ports. :-)

Dan

Re: [gentoo-user] Why my wierd ifconfig setup won't work in iproute2... ever.

[Walter Dnes]

On Sun, Mar 01, 2015 at 08:36:42AM -0800, Daniel Frey wrote

> I got my HDHomerun tuner around then too, but I decided back then
> (without reading the manual) that I didn't want it on my "main" NIC, so
> I bought an Intel pci-e NIC and dedicated the Homerun to it.
> 
> Every once in a while I move the computer (unplugging everything) and
> when I go to plug it back in I can never remember which network port is
> which. I should really label those ports. :-)

  I tried it just now, and DHCP does work, notwithstanding all the
(non)documentation and no mention of DHCP in the "get help" output.  I
turned on my router's DHCP server, increased my LAN subnet from /29 to
/28, reflected that in iptables rules, and things work.  Maybe this
feature was backported in a firmware update.  I'm running the latest
firmware for the HDHR-US.  The linux download is...
http://download.silicondust.com/hdhomerun/hdhomerun_atsc_firmware_20141124.bin

-- 
Walter Dnes <waltdnes@waltdnes.org>
I don't run "desktop environments"; I run useful applications

Re: [gentoo-user] Why my wierd ifconfig setup won't work in iproute2... ever.

[Stroller]

On Sun, 1 March 2015, at 3:22 am, Walter Dnes <waltdnes@waltdnes.org> wrote:
> 
> * My only option in an iproute2-only environment would be to get a 2nd
>  NIC and attach the TV tuner to it.
> 
> * My HDHomerun tuner is almost a museum-piece (spring of 2010).  I
>  figure that by the time ifconfig support is finally deprecated, I'll
>  be looking for a new tuner, rather than buying another NIC.

About 10 days ago, Mick already suggested you configure you HDhomerun with a more appropriate IP address.

http://archives.gentoo.org/gentoo-user/message/61171ddc1dfe80924ebc833060d06734

I have not seen you address this. I cannot comprehend why not.

A 169.254.x.y address is wrong. You should give the tuner a 192.168.123.z address.

Stroller.

Re: [gentoo-user] Why my wierd ifconfig setup won't work in iproute2... ever.

[Mick]

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On Monday 02 Mar 2015 00:33:11 Stroller wrote:
> On Sun, 1 March 2015, at 3:22 am, Walter Dnes <waltdnes@waltdnes.org> wrote:
> > * My only option in an iproute2-only environment would be to get a 2nd
> > 
> >  NIC and attach the TV tuner to it.
> > 
> > * My HDHomerun tuner is almost a museum-piece (spring of 2010).  I
> > 
> >  figure that by the time ifconfig support is finally deprecated, I'll
> >  be looking for a new tuner, rather than buying another NIC.
> 
> About 10 days ago, Mick already suggested you configure you HDhomerun with
> a more appropriate IP address.
> 
> http://archives.gentoo.org/gentoo-user/message/61171ddc1dfe80924ebc833060d0
> 6734
> 
> I have not seen you address this. I cannot comprehend why not.
> 
> A 169.254.x.y address is wrong. You should give the tuner a 192.168.123.z
> address.
> 
> Stroller.

You seemed to have missed Walter's response, where explained a couple of days 
ago that his tuner is too old and lacks the functionality to use anything else 
but an autoconfigured address:

http://article.gmane.org/gmane.linux.gentoo.user/281174

-- 
Regards,
Mick

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[gentoo-user] DHCP is a "hidden feature" / "easter egg"

[Walter Dnes]

On Mon, Mar 02, 2015 at 12:33:11AM +0000, Stroller wrote

> About 10 days ago, Mick already suggested you configure you HDhomerun with a more appropriate IP address.
> 
> http://archives.gentoo.org/gentoo-user/message/61171ddc1dfe80924ebc833060d06734
> 
> I have not seen you address this. I cannot comprehend why not.

  This is what I get for TTFM (Trusting The Fine Manual). I did Google
and RTFM.  Page 6 of the PDF document at the manufacturer's website...
http://www.silicondust.com/hdhomerun/hdhomerun_tech.pdf lists the output
from a "get help" command ***FOR CURRENT MODELS***.  It includes,
amongst other items...

/sys/ipaddr dhcp|"<ip> <mask> <gw> <dns>"

  On my machine, "get help" produces...

Supported configuration options:
/ir/target <protocol>://<ip>:<port>
/lineup/location <countrycode>:<postcode>
/sys/copyright
/sys/debug
/sys/features
/sys/hwmodel
/sys/model
/sys/restart <resource>
/sys/version
/tuner<n>/channel <modulation>:<freq|ch>
/tuner<n>/channelmap <channelmap>
/tuner<n>/debug
/tuner<n>/filter "0x<nnnn>-0x<nnnn> [...]"
/tuner<n>/lockkey
/tuner<n>/program <program number>
/tuner<n>/streaminfo
/tuner<n>/status
/tuner<n>/target <ip>:<port>

  There is no mention of "/sys/ipaddr" ***ON MY MACHINE***.  I also
remember various people asking on the HDHomerun support forum years ago
about IP addresses, and hearing that this model did not have any other
addressing options.  One correction on the date of my machine.   See
https://www.youtube.com/watch?v=JXmi-6nVhCM which discusses the exact
same model I have.  I bought mine in 2010, but the reviewer notes that
it won some award at CES2008.  Consider it a 2008 model.

  Due to the documentation, and lack of mention of DHCP in "get help", I
assumed it wouldn't work.  However, just for ####s and giggles, I
enabled the DHCP server on my router, set the DHCP address pool to
192.168.123.241-to-192.168.123.247, and expanded my local LAN subnet
from a /29 to a /28 like so...

config_eth0="
192.168.123.251/28 broadcast 192.168.123.255"
routes_eth0="
default via 192.168.123.254 metric 20
192.168.123.240/28 via 192.168.123.254 metric 0"

  Notice the lack of a 'modules=( "!iproute2" )' line.  I installed the
latest firmware update from the manufacturer's website...
(hdhomerun_atsc_firmware_20141124.bin).  Lo and behold, it actually
works, coming up at 192.168.123.241.  This is notwithstanding the
documentation and "get help" output, which both say nothing about DHCP.
Maybe this was a feature that was backported into a firmware update.
Anyhow, I apologize for wasting peoples' time.

-- 
Walter Dnes <waltdnes@waltdnes.org>
I don't run "desktop environments"; I run useful applications

Re: [gentoo-user] Re: [SOLVED] What happened to my 2nd eth0?

[Mick]

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On Thursday 26 Feb 2015 18:57:44 Walter Dnes wrote:
>   Let's forget about additional routes with different metrics, and try
> to get the simplest case working, and move forward from there.  If I have
> /etc/conf.d/net as...
> 
> modules=( "!iproute2" )  <== Delete this for iproute2 usage ==
> config_eth0="
> 192.168.123.251/29 broadcast 192.168.123.255
> 169.254.1.1/16 broadcast 169.254.255.255"
> routes_eth0="
> default via 192.168.123.254
169.254.0.0/16 via 169.254.1.1"  <==Add this route for 169.254.0.0/16==

or if your router can route packets for the 169.254.0.0/16 subnet (I doubt it) 
then change it to:

169.254.0.0/16 via 192.168.123.254


>   I'm still trying to wrap my brain around how the ADSL router decides
> whether to look for 169.254.0.0/16 on the ethernet cable to the TV tuner
> rather than on the phone line going to my ISP, and then the world.

If the router has link-local configured it should be able to communicate with 
other devices in the same 169.254.0.0/16 subnet.  However, I doubt that it 
will be NAT-ing packets to this subnet, because it is meant for ad-hoc device-
to-device connections when there is no DHCP server in the local network.

Have a look at the router's route and arp tables to see what it does on this 
matter.

-- 
Regards,
Mick

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Re: [gentoo-user] Re: [SOLVED] What happened to my 2nd eth0?

[Walter Dnes]

On Tue, Feb 24, 2015 at 06:43:19AM +0000, Mick wrote

> PS.  Did you look at setting your desired subnet rather than a
> local-link auto-configured address at your HDHomerun device?

  No go.  I have an ancient HDHR-US model.  The output from "get help"
is...

Supported configuration options:
/ir/target <protocol>://<ip>:<port>
/lineup/location <countrycode>:<postcode>
/sys/copyright
/sys/debug
/sys/features
/sys/hwmodel
/sys/model
/sys/restart <resource>
/sys/version
/tuner<n>/channel <modulation>:<freq|ch>
/tuner<n>/channelmap <channelmap>
/tuner<n>/debug
/tuner<n>/filter "0x<nnnn>-0x<nnnn> [...]"
/tuner<n>/lockkey
/tuner<n>/program <program number>
/tuner<n>/streaminfo
/tuner<n>/status
/tuner<n>/target <ip>:<port>

  According to the manufacturer's site, the latest models support a lot
more stuff, including...

/sys/ipaddr dhcp|"<ip> <mask> <gw> <dns>"

... which allows to get/set ipaddress, or work as a dhcp client.

-- 
Walter Dnes <waltdnes@waltdnes.org>
I don't run "desktop environments"; I run useful applications

Re: [gentoo-user] What happened to my 2nd eth0?

[Tom H]

On Sat, Feb 21, 2015 at 11:52 PM, Walter Dnes <waltdnes@waltdnes.org> wrote:


> My DSL router modem is at 192.168.123.254. I have an HDHomerun
> network TV tuner that insists on coming up somewhere in the 169.254.X.Y
> block. Up until upgrading from 32 to 64 bits, I was able to see a 2nd
> eth0 (i.e. eth0:1) using the following /etc/conf.d/net setup...
>
> config_eth0="
> 192.168.123.251/29 broadcast 192.168.123.255
> 169.254.1.1/16 broadcast 169.254.255.255"
> routes_eth0="
> default via 192.168.123.254 metric 20
> 192.168.123.248/29 via 192.168.123.254 metric 0
> 169.254.0.0/16 via 169.254.1.1 metric 0"
>
> The 2nd interface is no longer being set up. As amatter of fact, it
> appears to be totally unavailable. E.g....
>
> [d531][root][~] /etc/init.d/net.eth0 stop
>  * Unmounting network filesystems ...                                     [ ok ]
>  * Bringing down interface eth0
> [d531][root][~] ifconfig eth0:0 192.168.123.251/29 broadcast 192.168.123.255
> SIOCSIFNETMASK: Cannot assign requested address

You cannot bring up an ip alias if the "base" ip address isn't set.


> [d531][root][~] ifconfig eth0 192.168.123.251/29 broadcast 192.168.123.255
> [d531][root][~]
>
> So my system doesn't support even the concept of an alias for eth0.
> Looking at the ifconfig manpage...
>
> interface
>        The  name  of the interface.  This is usually a driver name fol-
>        lowed by a unit number, for example eth0 for the first  Ethernet
>        interface.  If  your  kernel  supports alias interfaces, you can
>        specify them with eth0:0 for the first alias of  eth0.  You  can
>        use  them  to assign a second address. To delete an alias inter-
>        face use ifconfig eth0:0 down.  Note: for every scope (i.e. same
>        net  with  address/netmask combination) all aliases are deleted,
>        if you delete the first (primary).
>
> I see "If  your  kernel  supports alias interfaces". During the
> upgrade, I built the kernel from square 1. I already ran into problems
> with not enabling FUSE in the new kernel, which killed MTP until I
> enabled it. I wouldn't be surprised if I've disabled some kernel
> parameter which is required to enable interface aliases. I didn't see
> anything obvious in "make menuconfig". A Google search turned up a
> gazillion examples of "how to create an alias using ifconfig". That's
> not what I want. I want the kernel setting that allows creating alias
> interfaces.

CONFIG_IP_ALIAS was dropped with v2.4

From 2.2 alias.txt:

For IP aliasing you must have IP_ALIAS support included by static
linking.

From 2.4 alias.txt:

IP-aliases are additional IP-adresses/masks hooked up to a base
interface by adding a colon and a string when running ifconfig.
This string is usually numeric, but this is not a must.

IP-Aliases are avail if CONFIG_INET (`standard' IPv4 networking)
is configured in the kernel.

From 3.19 alias.txt:

IP-aliases are an obsolete way to manage multiple IP-addresses/masks
per interface. Newer tools such as iproute2 support multiple
address/prefixes per interface, but aliases are still supported
for backwards compatibility.