From b281952f933017066936ae329f300f61d4f135a4 Mon Sep 17 00:00:00 2001 From: Gordon Hollingworth Date: Thu, 3 Jan 2019 14:35:46 +0000 Subject: [PATCH 1/2] Document network booting bugs --- hardware/raspberrypi/bootmodes/net.md | 37 +++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) diff --git a/hardware/raspberrypi/bootmodes/net.md b/hardware/raspberrypi/bootmodes/net.md index 65a654036..d4d806532 100644 --- a/hardware/raspberrypi/bootmodes/net.md +++ b/hardware/raspberrypi/bootmodes/net.md @@ -98,5 +98,42 @@ You will know whether the Vendor Option is correctly specified: if it is, you'll 192.168.1.139.49152 > 192.168.1.1.55985: [no cksum] UDP, length 4 ``` +## Known problems + +There are a number of known problems with the Ethernet boot mode. Since the implementation of the boot modes is in the chip itself then there are no work arounds, other than to use an SD card with just the bootcode.bin file. + +### DHCP requests time out after five tries + +The Raspberry Pi will attempt a DHCP request five times with five seconds between, for a total period of 25 seconds. If the server is not available to respond in this time then the Pi will drop into a low power state. This has no workaround, other than bootcode.bin on an SD card. + +### TFTP server on separate subnet not supported + +Fixed in Raspberry Pi 3 Model B+ (BCM2837B0) + +### DHCP relay broken + +The DHCP check also checked if the hops value was '1' which it wouldn't be with DHCP relay. + +Fixed in Raspberry Pi 3 Model B+ + +### Raspberry Pi Boot string + +The "Raspberry Pi Boot " string in the DHCP reply requires the extra three spaces due to an error calculating the string length. + +Fixed in Raspberry Pi 3 Model B+ + +### DHCP UUID constant + +The DHCP UUID is set to be a constant value + +Fixed in Raspberry Pi 3 Model B+, the value is set to the 32 bit serial number + +### ARP check can fail to respond in the middle of TFTP transaction + +The Raspberry Pi will only respond to ARP requests when it is in the initialsation phase, once it has begun transferring data it'll fail to continue reponding. + +Fixed in Raspberry Pi 3 Model B+ + + See Also: * [Network boot tutorial](net_tutorial.md) From aac64c801b5fa0a1cd685f8cd474dac141ed1a2e Mon Sep 17 00:00:00 2001 From: JaninaPi Date: Thu, 10 Jan 2019 14:44:25 +0000 Subject: [PATCH 2/2] copy edits --- hardware/raspberrypi/bootmodes/net.md | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/hardware/raspberrypi/bootmodes/net.md b/hardware/raspberrypi/bootmodes/net.md index d4d806532..f3f5f0a06 100644 --- a/hardware/raspberrypi/bootmodes/net.md +++ b/hardware/raspberrypi/bootmodes/net.md @@ -100,21 +100,21 @@ You will know whether the Vendor Option is correctly specified: if it is, you'll ## Known problems -There are a number of known problems with the Ethernet boot mode. Since the implementation of the boot modes is in the chip itself then there are no work arounds, other than to use an SD card with just the bootcode.bin file. +There are a number of known problems with the Ethernet boot mode. Since the implementation of the boot modes is in the chip itself, there are no workarounds other than to use an SD card with just the bootcode.bin file. ### DHCP requests time out after five tries -The Raspberry Pi will attempt a DHCP request five times with five seconds between, for a total period of 25 seconds. If the server is not available to respond in this time then the Pi will drop into a low power state. This has no workaround, other than bootcode.bin on an SD card. +The Raspberry Pi will attempt a DHCP request five times with five seconds in between, for a total period of 25 seconds. If the server is not available to respond in this time, then the Pi will drop into a low-power state. There is no workaround for this other than bootcode.bin on an SD card. ### TFTP server on separate subnet not supported -Fixed in Raspberry Pi 3 Model B+ (BCM2837B0) +Fixed in Raspberry Pi 3 Model B+ (BCM2837B0). ### DHCP relay broken -The DHCP check also checked if the hops value was '1' which it wouldn't be with DHCP relay. +The DHCP check also checked if the hops value was `1`, which it wouldn't be with DHCP relay. -Fixed in Raspberry Pi 3 Model B+ +Fixed in Raspberry Pi 3 Model B+. ### Raspberry Pi Boot string @@ -124,16 +124,16 @@ Fixed in Raspberry Pi 3 Model B+ ### DHCP UUID constant -The DHCP UUID is set to be a constant value +The DHCP UUID is set to be a constant value. -Fixed in Raspberry Pi 3 Model B+, the value is set to the 32 bit serial number +Fixed in Raspberry Pi 3 Model B+; the value is set to the 32-bit serial number. ### ARP check can fail to respond in the middle of TFTP transaction -The Raspberry Pi will only respond to ARP requests when it is in the initialsation phase, once it has begun transferring data it'll fail to continue reponding. +The Raspberry Pi will only respond to ARP requests when it is in the initialsation phase; once it has begun transferring data, it'll fail to continue reponding. -Fixed in Raspberry Pi 3 Model B+ +Fixed in Raspberry Pi 3 Model B+. -See Also: +See also: * [Network boot tutorial](net_tutorial.md)