package/skeleton: add a startup script to wait for slow network interfaces

PATCH New Yann E. MORIN 6 participants 13 messages Oct 3, 2015 – Oct 19, 2015

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Yann E. MORIN

author

2015-10-03 13:31 UTC #0 lore raw

PATCH 1/1 package/skeleton: add a startup script to wait for slow network interfaces

On some machines, the network interface is slow to appear. For example, on the Raspberry Pi, the network interface eth0 is an ethernet-over-USB, and our standard boot process is too fast, so our network startup script is called before the USB bus is compeltely enumerated, thus it can't configure eth0.

If Buildroot is configured to do a DHCP on an interface, install a startup script, just before S40network, that waits for that interface.

Since Buildroot can only be configured to run DHCP on a single interface, we do not need a script that waits for more than one interface.

Closes #8116.

Signed-off-by "Yann E. MORIN" <[email protected]>

---
 package/skeleton/S39wait-for-network-if | 43 +++++++++++++++++++++++++++++++++
 package/skeleton/skeleton.mk            |  2 ++
 2 files changed, 45 insertions(+)
 create mode 100644 package/skeleton/S39wait-for-network-if

package/skeleton/S39wait-for-network-if new file +43 -0

new file mode 100644
index 0000000..010026e
@@ -0,0 +1,43 @@
+#!/bin/sh
+
+# In case we have a slow-to-appear interface (e.g. eth-over-USB),
+# and we need to configure it, wait until it appears. But not too
+# long either. WAIT_DELAY is in seconds.
+WAIT_DELAY=15
+
+wait_for_IF() {
+    IF="$(sed -r -e '/^auto lo/d;' \
+                 -e '/^auto (.+)$/!d;' \
+                 -e 's//\1/;' \
+                 /etc/network/interfaces
+         )"
+    if [ -z "${IF}" -o -e "/sys/class/net/${IF}" ]; then
+        return 0
+    fi
+    printf "Waiting for interface %s to appear" "${IF}"
+    wait=${WAIT_DELAY}
+    while [ ${wait} -gt 0 ]; do
+        if [ -e "/sys/class/net/${IF}" ]; then
+            printf " yes\n"
+            return 0
+        fi
+        sleep 1
+        printf "."
+        : $((wait--))
+    done
+    printf " no.\n"
+    return 1
+}
+
+case "$1" in
+  start)
+	wait_for_IF
+	;;
+  stop)
+	;;
+  restart)
+	"$0" start
+	;;
+  *)
+	echo "Usage: $0 {start|stop|restart}"
+esac

package/skeleton/skeleton.mk +2 -0

index 48e7085..733b86f 100644
@@ -76,6 +76,8 @@ define SET_NETWORK_DHCP
 		echo "auto $(NETWORK_DHCP_IFACE)";                   \
 		echo "iface $(NETWORK_DHCP_IFACE) inet dhcp";        \
 	) >> $(TARGET_DIR)/etc/network/interfaces
+	$(INSTALL) -D -m 0755 package/skeleton/S39wait-for-network-if \
+		$(TARGET_DIR)/etc/init.d/S39wait-for-network-if
 endef
 endif

Signature · 1 line

1.9.1

Arnout Vandecappelle

2015-10-03 13:51 UTC #1 lore raw

PATCH 1/1 package/skeleton: add a startup script to wait for slow network interfaces

Quoted 9 lines · Yann E. MORIN

On some machines, the network interface is slow to appear. For example, on the Raspberry Pi, the network interface eth0 is an ethernet-over-USB, and our standard boot process is too fast, so our network startup script is called before the USB bus is compeltely enumerated, thus it can't configure eth0.
If Buildroot is configured to do a DHCP on an interface, install a startup script, just before S40network, that waits for that interface.

Quoted 8 lines

Since Buildroot can only be configured to run DHCP on a single interface, we do not need a script that waits for more than one interface.
Closes #8116.
Signed-off-by "Yann E. MORIN" <[email protected]>
---
 package/skeleton/S39wait-for-network-if | 43 +++++++++++++++++++++++++++++++++

Argh, you're adding an init script to skeleton! That's evil(TM)! :-)

Seriously, this should be part of package/initscripts/init.d/S40network instead.

Quoted 10 lines

 package/skeleton/skeleton.mk            |  2 ++
 2 files changed, 45 insertions(+)
 create mode 100644 package/skeleton/S39wait-for-network-if

package/skeleton/S39wait-for-network-if new file +0 -0

new file mode 100644
index 0000000..010026e

package/skeleton/S39wait-for-network-if line 9

Quoted 9 lines

package/skeleton/S39wait-for-network-if new file +9 -0

@@ -0,0 +1,43 @@
+#!/bin/sh
+
+# In case we have a slow-to-appear interface (e.g. eth-over-USB),
+# and we need to configure it, wait until it appears. But not too
+# long either. WAIT_DELAY is in seconds.
+WAIT_DELAY=15
+
+wait_for_IF() {
+    IF="$(sed -r -e '/^auto lo/d;' \

I believe the ; are redundant when you use -e (at least that's what we do in
other cases).

package/skeleton/S39wait-for-network-if line 11

Quoted 2 lines

package/skeleton/S39wait-for-network-if new file +2 -0
+                 -e '/^auto (.+)$/!d;' \
+                 -e 's//\1/;' \

This one got me looking at the sed man page and I'm still surprised that it
works. Basically, this s command is reusing the same address as given on the previous line, but without the ! modifier, right?

Regards,
Arnout

Quoted 46 lines

package/skeleton/S39wait-for-network-if new file +32 -0

+                 /etc/network/interfaces
+         )"
+    if [ -z "${IF}" -o -e "/sys/class/net/${IF}" ]; then
+        return 0
+    fi
+    printf "Waiting for interface %s to appear" "${IF}"
+    wait=${WAIT_DELAY}
+    while [ ${wait} -gt 0 ]; do
+        if [ -e "/sys/class/net/${IF}" ]; then
+            printf " yes\n"
+            return 0
+        fi
+        sleep 1
+        printf "."
+        : $((wait--))
+    done
+    printf " no.\n"
+    return 1
+}
+
+case "$1" in
+  start)
+	wait_for_IF
+	;;
+  stop)
+	;;
+  restart)
+	"$0" start
+	;;
+  *)
+	echo "Usage: $0 {start|stop|restart}"
+esac

package/skeleton/skeleton.mk +2 -0

index 48e7085..733b86f 100644
@@ -76,6 +76,8 @@ define SET_NETWORK_DHCP
 		echo "auto $(NETWORK_DHCP_IFACE)";                   \
 		echo "iface $(NETWORK_DHCP_IFACE) inet dhcp";        \
 	) >> $(TARGET_DIR)/etc/network/interfaces
+	$(INSTALL) -D -m 0755 package/skeleton/S39wait-for-network-if \
+		$(TARGET_DIR)/etc/init.d/S39wait-for-network-if
 endef
 endif

Signature · 6 lines

Arnout Vandecappelle                          arnout at mind be
Senior Embedded Software Architect            +32-16-286500
Essensium/Mind                                http://www.mind.be
G.Geenslaan 9, 3001 Leuven, Belgium           BE 872 984 063 RPR Leuven
LinkedIn profile: http://www.linkedin.com/in/arnoutvandecappelle
GPG fingerprint:  7493 020B C7E3 8618 8DEC 222C 82EB F404 F9AC 0DDF

Peter Korsgaard

2015-10-03 13:59 UTC #2 lore raw

PATCH 1/1 package/skeleton: add a startup script to wait for slow network interfaces

In reply to Yann E. MORIN

Quoted 8 lines

Quoted 1 line
Quoted 1 line
Quoted 1 line
Quoted 1 line
"Yann" == Yann E MORIN <[email protected]> writes:
On some machines, the network interface is slow to appear. For example, on the Raspberry Pi, the network interface eth0 is an ethernet-over-USB, and our standard boot process is too fast, so our network startup script is called before the USB bus is compeltely enumerated, thus it can't configure eth0.

Quoted 7 lines

If Buildroot is configured to do a DHCP on an interface, install a startup script, just before S40network, that waits for that interface.
Since Buildroot can only be configured to run DHCP on a single interface, we do not need a script that waits for more than one interface.
Closes #8116.

A more generic solution for dynamic changes to network interfaces is to NOT mark them as auto and instead use ifplugd -M <interface>.

Quoted 16 lines

Signed-off-by "Yann E. MORIN" <[email protected]>

---
 package/skeleton/S39wait-for-network-if | 43 +++++++++++++++++++++++++++++++++
 package/skeleton/skeleton.mk            |  2 ++
 2 files changed, 45 insertions(+)
 create mode 100644 package/skeleton/S39wait-for-network-if

package/skeleton/S39wait-for-network-if new file +3 -0

new file mode 100644
index 0000000..010026e
@@ -0,0 +1,43 @@
+#!/bin/sh
+
+# In case we have a slow-to-appear interface (e.g. eth-over-USB),

package/skeleton/S39wait-for-network-if line 13

Quoted 10 lines

package/skeleton/S39wait-for-network-if new file +10 -0

+# and we need to configure it, wait until it appears. But not too
+# long either. WAIT_DELAY is in seconds.
+WAIT_DELAY=15
+
+wait_for_IF() {
+    IF="$(sed -r -e '/^auto lo/d;' \
+                 -e '/^auto (.+)$/!d;' \
+                 -e 's//\1/;' \
+                 /etc/network/interfaces
+         )"

This assumes we have at most 1 interface to wait for.

Perhaps we could instead do something like (untested):

IFACES=$(awk '/^auto/ { print $2 }' /tmp/interfaces)

for i in $(seq $WAIT_DELAY); do
for IFACE in $IFACES; do
if [ ! -e "/tmp/$IFACE" ]; then
sleep 1
continue 2
fi
done

echo "ok"; exit 0
done

echo "timeout"; exit 1

Signature · 1 line

Bye, Peter Korsgaard

Peter Korsgaard

2015-10-03 14:01 UTC #3 lore raw

PATCH 1/1 package/skeleton: add a startup script to wait for slow network interfaces

Quoted 9 lines

package/skeleton/S39wait-for-network-if line 13
Quoted 8 lines
Quoted 1 line
Quoted 1 line
Quoted 1 line
"Peter" == Peter Korsgaard <[email protected]> writes:
package/skeleton/S39wait-for-network-if new file +6 -0
+wait_for_IF() {
+    IF="$(sed -r -e '/^auto lo/d;' \
+                 -e '/^auto (.+)$/!d;' \
+                 -e 's//\1/;' \
+                 /etc/network/interfaces
+         )"

Quoted 5 lines

This assumes we have at most 1 interface to wait for.
Perhaps we could instead do something like (untested):
IFACES=$(awk '/^auto/ { print $2 }' /tmp/interfaces)

That should naturally be /etc/network/interfaces

Quoted 3 lines

for i in $(seq $WAIT_DELAY); do
for IFACE in $IFACES; do
if [ ! -e "/tmp/$IFACE" ]; then

and /sys/class/net/$IFACE

See, I did actually do a quick test after all ;)

Signature · 1 line

Bye, Peter Korsgaard

Peter Korsgaard

2015-10-16 09:42 UTC #4 lore raw

PATCH 1/1 package/skeleton: add a startup script to wait for slow network interfaces

In reply to Peter Korsgaard

Quoted 31 lines

Quoted 9 lines
Quoted 3 lines
Quoted 3 lines
Quoted 3 lines
"Peter" == Peter Korsgaard <[email protected]> writes:
"Yann" == Yann E MORIN <[email protected]> writes:
On some machines, the network interface is slow to appear. For example, on the Raspberry Pi, the network interface eth0 is an ethernet-over-USB, and our standard boot process is too fast, so our network startup script is called before the USB bus is compeltely enumerated, thus it can't configure eth0.
Quoted 7 lines
If Buildroot is configured to do a DHCP on an interface, install a startup script, just before S40network, that waits for that interface.
Since Buildroot can only be configured to run DHCP on a single interface, we do not need a script that waits for more than one interface.
Closes #8116.
This assumes we have at most 1 interface to wait for.
Perhaps we could instead do something like (untested):
IFACES=$(awk '/^auto/ { print $2 }' /tmp/interfaces)
for i in $(seq $WAIT_DELAY); do
for IFACE in $IFACES; do
if [ ! -e "/tmp/$IFACE" ]; then
sleep 1
continue 2
fi
done

Quoted 4 lines

echo "ok"; exit 0
done
echo "timeout"; exit 1

Committed after moving it to S40network and changing the implementation to support multiple interaces, thanks.

Signature · 1 line

Bye, Peter Korsgaard

Thomas Petazzoni

2015-10-03 15:47 UTC #5 lore raw

PATCH 1/1 package/skeleton: add a startup script to wait for slow network interfaces

In reply to Yann E. MORIN

Hello,

package/skeleton/S39wait-for-network-if line 27

Quoted 11 lines · Yann E. MORIN

package/skeleton/S39wait-for-network-if new file +11 -0

+    printf "Waiting for interface %s to appear" "${IF}"
+    wait=${WAIT_DELAY}
+    while [ ${wait} -gt 0 ]; do
+        if [ -e "/sys/class/net/${IF}" ]; then
+            printf " yes\n"
+            return 0
+        fi
+        sleep 1
+        printf "."
+        : $((wait--))
+    done

One thing that I really like in Buildroot is that by default, it generates you a system that boots really fast. People often don't have to do anything special with Buildroot to make it boot fast. So having a shell script that is installed by default and does a "sleep 1" in a loop is not very nice :-/

Though I agree that it will only slow the boot on systems where the network interfaces are not available immediately at boot time.

Thomas

Signature · 3 lines

Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

Maxime Hadjinlian

2015-10-03 18:29 UTC #6 lore raw

PATCH 1/1 package/skeleton: add a startup script to wait for slow network interfaces

Quoted 16 lines · Thomas Petazzoni

Hello,

package/skeleton/S39wait-for-network-if line 27

Quoted 11 lines · Yann E. MORIN

package/skeleton/S39wait-for-network-if new file +11 -0

+    printf "Waiting for interface %s to appear" "${IF}"
+    wait=${WAIT_DELAY}
+    while [ ${wait} -gt 0 ]; do
+        if [ -e "/sys/class/net/${IF}" ]; then
+            printf " yes\n"
+            return 0
+        fi
+        sleep 1
+        printf "."
+        : $((wait--))
+    done

Quoted 9 lines

One thing that I really like in Buildroot is that by default, it generates you a system that boots really fast. People often don't have to do anything special with Buildroot to make it boot fast. So having a shell script that is installed by default and does a "sleep 1" in a loop is not very nice :-/
Though I agree that it will only slow the boot on systems where the network interfaces are not available immediately at boot time.

I have that trouble too but instead of doing a sleep 1, I "hammer" the system with sleep 0.1 or usleep 25 if it's available (even usleep 1 can work, since it's not RT, it takes around 10ms).
This way it's almost transparent and add the necessary requirements before going on with the boot.

Quoted 11 lines

Thomas
--
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
_______________________________________________
buildroot mailing list
buildroot at busybox.net
http://lists.busybox.net/mailman/listinfo/buildroot

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Arnout Vandecappelle

2015-10-03 18:43 UTC #7 lore raw

PATCH 1/1 package/skeleton: add a startup script to wait for slow network interfaces

Quoted 28 lines · Maxime Hadjinlian

On Sat, Oct 3, 2015 at 5:47 PM, Thomas Petazzoni <[email protected] <mailto:[email protected]>> wrote:
Hello,
On Sat, 3 Oct 2015 14:31:45 +0100, Yann E. MORIN wrote:
> + printf "Waiting for interface %s to appear" "${IF}"
> + wait=${WAIT_DELAY}
> + while [ ${wait} -gt 0 ]; do
> + if [ -e "/sys/class/net/${IF}" ]; then
> + printf " yes\n"
> + return 0
> + fi
> + sleep 1
> + printf "."
> + : $((wait--))
> + done
One thing that I really like in Buildroot is that by default, it generates you a system that boots really fast. People often don't have to do anything special with Buildroot to make it boot fast. So having a shell script that is installed by default and does a "sleep 1" in a loop is not very nice :-/

Quoted 6 lines

Though I agree that it will only slow the boot on systems where the network interfaces are not available immediately at boot time.
I have that trouble too but instead of doing a sleep 1, I "hammer" the system with sleep 0.1 or usleep 25 if it's available (even usleep 1 can work, since it's not RT, it takes around 10ms).

Since sysv init is not parallel, you're not even hammering the system since
nothing else is going on except perhaps some hotplug callbacks.

Regards,
Arnout

Quoted 22 lines

This way it's almost transparent and add the necessary requirements before going on with the boot.
Thomas
--
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
_______________________________________________
buildroot mailing list
buildroot at busybox.net <mailto:[email protected]>
http://lists.busybox.net/mailman/listinfo/buildroot
_______________________________________________
buildroot mailing list
buildroot at busybox.net
http://lists.busybox.net/mailman/listinfo/buildroot

Signature · 6 lines

Arnout Vandecappelle                          arnout at mind be
Senior Embedded Software Architect            +32-16-286500
Essensium/Mind                                http://www.mind.be
G.Geenslaan 9, 3001 Leuven, Belgium           BE 872 984 063 RPR Leuven
LinkedIn profile: http://www.linkedin.com/in/arnoutvandecappelle
GPG fingerprint:  7493 020B C7E3 8618 8DEC 222C 82EB F404 F9AC 0DDF

Maxime Hadjinlian

2015-10-03 18:46 UTC #8 lore raw

PATCH 1/1 package/skeleton: add a startup script to wait for slow network interfaces

Quoted 35 lines · Arnout Vandecappelle

Quoted 22 lines · Maxime Hadjinlian
On Sat, Oct 3, 2015 at 5:47 PM, Thomas Petazzoni <[email protected] <mailto:[email protected]>> wrote:
Hello,
On Sat, 3 Oct 2015 14:31:45 +0100, Yann E. MORIN wrote:
> + printf "Waiting for interface %s to appear" "${IF}"
> + wait=${WAIT_DELAY}
> + while [ ${wait} -gt 0 ]; do
> + if [ -e "/sys/class/net/${IF}" ]; then
> + printf " yes\n"
> + return 0
> + fi
> + sleep 1
> + printf "."
> + : $((wait--))
> + done
Quoted 2 lines
One thing that I really like in Buildroot is that by default, it generates you a system that boots really fast. People often don't
have
Quoted 1 line
to do anything special with Buildroot to make it boot fast. So
having a
Quoted 7 lines
shell script that is installed by default and does a "sleep 1" in a loop is not very nice :-/
Though I agree that it will only slow the boot on systems where the network interfaces are not available immediately at boot time.
I have that trouble too but instead of doing a sleep 1, I "hammer" the

Quoted 9 lines

system
Quoted 1 line
with sleep 0.1 or usleep 25 if it's available (even usleep 1 can work,
since
Quoted 1 line
it's not RT, it takes around 10ms).
Since sysv init is not parallel, you're not even hammering the system
since
nothing else is going on except perhaps some hotplug callbacks.

sysv is not, but the shell is. The scripts are started in background and then I simply use wait

Quoted 29 lines

Regards,
Arnout
Quoted 1 line
This way it's almost transparent and add the necessary requirements
before going
Quoted 16 lines
on with the boot.
Thomas
--
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
_______________________________________________
buildroot mailing list
buildroot at busybox.net <mailto:[email protected]>
http://lists.busybox.net/mailman/listinfo/buildroot
Quoted 5 lines
_______________________________________________
buildroot mailing list
buildroot at busybox.net
http://lists.busybox.net/mailman/listinfo/buildroot

Quoted 8 lines

Arnout Vandecappelle                          arnout at mind be
Senior Embedded Software Architect            +32-16-286500
Essensium/Mind                                http://www.mind.be
G.Geenslaan 9, 3001 Leuven, Belgium           BE 872 984 063 RPR Leuven
LinkedIn profile: http://www.linkedin.com/in/arnoutvandecappelle
GPG fingerprint:  7493 020B C7E3 8618 8DEC 222C 82EB F404 F9AC 0DDF

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Peter Korsgaard

2015-10-04 08:23 UTC #9 lore raw

PATCH 1/1 package/skeleton: add a startup script to wait for slow network interfaces

In reply to Thomas Petazzoni

Quoted 17 lines

Quoted 1 line
Quoted 1 line
Quoted 1 line
Quoted 1 line
"Thomas" == Thomas Petazzoni <[email protected]> writes:
Hello,
package/skeleton/S39wait-for-network-if line 27
Quoted 11 lines · Yann E. MORIN
package/skeleton/S39wait-for-network-if new file +11 -0
+    printf "Waiting for interface %s to appear" "${IF}"
+    wait=${WAIT_DELAY}
+    while [ ${wait} -gt 0 ]; do
+        if [ -e "/sys/class/net/${IF}" ]; then
+            printf " yes\n"
+            return 0
+        fi
+        sleep 1
+        printf "."
+        : $((wait--))
+    done

Quoted 8 lines

One thing that I really like in Buildroot is that by default, it generates you a system that boots really fast. People often don't have to do anything special with Buildroot to make it boot fast. So having a shell script that is installed by default and does a "sleep 1" in a loop is not very nice :-/
Though I agree that it will only slow the boot on systems where the network interfaces are not available immediately at boot time.

Or where you misconfigured /etc/network/interfaces or forgot to enable the needed drivers in the kernel, but yeah.

But yes, using something like ifplugd to handle the interface when it shows up (or link state changes) is certainly nicer than just waiting.

Signature · 1 line

Bye, Peter Korsgaard

Jérôme Pouiller

2015-10-19 08:47 UTC #10 lore raw

PATCH 1/1 package/skeleton: add a startup script to wait for slow network interfaces

In reply to Yann E. MORIN

Hello Yann,

Quoted 62 lines · On Saturday 03 October 2015 14:31:45 Yann E. MORIN wrote:

On some machines, the network interface is slow to appear. For example, on the Raspberry Pi, the network interface eth0 is an ethernet-over-USB, and our standard boot process is too fast, so our network startup script is called before the USB bus is compeltely enumerated, thus it can't configure eth0.
If Buildroot is configured to do a DHCP on an interface, install a startup script, just before S40network, that waits for that interface.
Since Buildroot can only be configured to run DHCP on a single interface, we do not need a script that waits for more than one interface.
Closes #8116.
Signed-off-by "Yann E. MORIN" <[email protected]>
---
 package/skeleton/S39wait-for-network-if | 43
+++++++++++++++++++++++++++++++++ package/skeleton/skeleton.mk       
    |  2 ++
 2 files changed, 45 insertions(+)
 create mode 100644 package/skeleton/S39wait-for-network-if
(quoted diff) +0 -0
b/package/skeleton/S39wait-for-network-if new file mode 100644 index 0000000..010026e
package/skeleton/S39wait-for-network-if new file +33 -0
@@ -0,0 +1,43 @@
+#!/bin/sh
+
+# In case we have a slow-to-appear interface (e.g. eth-over-USB),
+# and we need to configure it, wait until it appears. But not too
+# long either. WAIT_DELAY is in seconds.
+WAIT_DELAY=15
+
+wait_for_IF() {
+    IF="$(sed -r -e '/^auto lo/d;' \
+                 -e '/^auto (.+)$/!d;' \
+                 -e 's//\1/;' \
+                 /etc/network/interfaces
+         )"
+    if [ -z "${IF}" -o -e "/sys/class/net/${IF}" ]; then
+        return 0
+    fi
+    printf "Waiting for interface %s to appear" "${IF}"
+    wait=${WAIT_DELAY}
+    while [ ${wait} -gt 0 ]; do
+        if [ -e "/sys/class/net/${IF}" ]; then
+            printf " yes\n"
+            return 0
+        fi
+        sleep 1
+        printf "."
+        : $((wait--))
+    done
+    printf " no.\n"
+    return 1
+}
+
+case "$1" in
+  start)

package/skeleton/S39wait-for-network-if line 43

Quoted 10 lines

package/skeleton/S39wait-for-network-if new file +10 -0

+	wait_for_IF
+	;;
+  stop)
+	;;
+  restart)
+	"$0" start
+	;;
+  *)
+	echo "Usage: $0 {start|stop|restart}"
+esac

I am a bit late to do the review, but why not add a script in /etc/network/if-pre-up.d ? For example (notice $IFACE and $IF_MAXWAIT are set by ifupdown):

#! /bin/sh
if [ "${IF_MAXWAIT}" ]; then

    printf "Waiting for interface %s to appear" "${IFACE}"
    while [ ${IF_MAXWAIT} -gt 0 ]; do
        if [ -e "/sys/class/net/${IFACE}" ]; then
            printf " yes\n"
            exit 0
        fi
        sleep 1
        printf "."
        : $((wait--))
    done
    printf " no.\n"
    exit 1

Next, interface would use "maxwait" property in /etc/network/interface:

auto eth0
iface eth0 inet dhcp
maxwait 15

BR,

Signature · 3 lines

J?r?me Pouiller, Sysmic
Embedded Linux specialist
http://www.sysmic.fr

Peter Korsgaard

2015-10-19 10:15 UTC #11 lore raw

PATCH 1/1 package/skeleton: add a startup script to wait for slow network interfaces

Quoted 1 line

Quoted 1 line
Quoted 1 line
Quoted 1 line
Quoted 1 line
"J?r?me" == J?r?me Pouiller <[email protected]> writes:

Hi,

Quoted 18 lines

I am a bit late to do the review, but why not add a script in /etc/network/if-pre-up.d ? For example (notice $IFACE and $IF_MAXWAIT are set by ifupdown):
#! /bin/sh
if [ "${IF_MAXWAIT}" ]; then
    printf "Waiting for interface %s to appear" "${IFACE}"
    while [ ${IF_MAXWAIT} -gt 0 ]; do
        if [ -e "/sys/class/net/${IFACE}" ]; then
            printf " yes\n"
            exit 0
        fi
        sleep 1
        printf "."
        : $((wait--))
    done
    printf " no.\n"
    exit 1

Quoted 1 line

fi

That's certainly also an option. Care to send a patch reworking the logic in S40network to a pre-up.d hook?

Quoted 5 lines

Next, interface would use "maxwait" property in /etc/network/interface:
auto eth0
iface eth0 inet dhcp
maxwait 15

Then our BR2_SYSTEM_DHCP logic should probably also be adapted to add 'maxwait 15' by default.

Thanks!

Signature · 1 line

Bye, Peter Korsgaard

Jérôme Pouiller

2015-10-19 10:22 UTC #12 lore raw

PATCH 1/1 package/skeleton: add a startup script to wait for slow network interfaces

Quoted 26 lines · On Monday 19 October 2015 12:15:40 Peter Korsgaard wrote:

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"J?r?me" == J?r?me Pouiller <[email protected]> writes:
Hi,
Quoted 23 lines
I am a bit late to do the review, but why not add a script in
/etc/network/if-pre-up.d ? For example (notice $IFACE and $IF_MAXWAIT
are set by ifupdown):
#! /bin/sh
if [ "${IF_MAXWAIT}" ]; then
    printf "Waiting for interface %s to appear" "${IFACE}"
    while [ ${IF_MAXWAIT} -gt 0 ]; do
    
        if [ -e "/sys/class/net/${IFACE}" ]; then
        
            printf " yes\n"
            exit 0
        
        fi
        sleep 1
        printf "."
        
        : $((wait--))

Quoted 8 lines

Quoted 5 lines
    done
    printf " no.\n"
    exit 1
fi
That's certainly also an option. Care to send a patch reworking the logic in S40network to a pre-up.d hook?

Ok, I will.

Signature · 3 lines

J?r?me Pouiller, Sysmic
Embedded Linux specialist
http://www.sysmic.fr