The good news: Barrier Breaker 14.07 works very well on the RB-450G. The device is built with good hardware, almost all of which is fully supported. The switch chipset (Atheros AR8316) however does not provide support for mixing tagged and untagged VLAN's on the same port. With a fast processor, gigabit ethernet, and relatively huge amounts of RAM and flash, this is a very capable device once OpenWRT is installed.
The bad news: getting OpenWRT installed in the first place is not straightforward (but almost).
OpenWrt doesn't provide a firmware image that can be written directly to the flash memory via the firmware update system in Mikrotik's RouterOS. So installing OpenWRT is a two step process that requires two separate kernel images.
You're going to need a desktop computer that has a working serial port (or adapter) and an ethernet interface. This computer will also need to have:
The following instructions illustrate installing Barrier Breaker 14.07, but should be easily adaptable to newer versions. For Attitude Adjustment 12.09 and previous it is required to build OpenWrt from source.
dnsmasqon the desktop computer.
bootp-filename, normally used to instruct a netboot device how to find its image. So you need to set up
dnsmasqwith specific options to work around this quirk.
openwrt-ar71xx-mikrotik-vmlinux-initramfs-lzma.elfto a clean directory like
~/tftproot/. Rename the file to
vmlinux(this helps when testing other images).
sudo dnsmasq -a 10.2.3.4 -z -d -p 0 -F 10.2.3.5,10.2.3.6 –enable-tftp –tftp-root=~/tftproot/ –dhcp-boot=~/tftproot/vmlinux.
dnsmasqshould start in the foreground writing all its output to the terminal; you're only going to run it temporarily, and having the debugging information may come in handy.
TIP: Try setting hardware flow control to off if you can't get to the bootloader menu (i.e. it always times out without detecting a key press). If using minicom, try
minicom -o –color=on –device=/dev/ttyS#, then once minicom opens, type
CONTROL A Z and find your way to disable hardware flow control. Or try
screen /dev/ttyS# 115200 To figure out which ttyS device you should use, the command
dmesg | grep ttyS can be helpful.
What do you want to configure? d - boot delay k - boot key s - serial console o - boot device u - cpu mode f - cpu frequency r - reset booter configuration e - format nand g - upgrade firmware i - board info p - boot protocol t - do memory testing x - exit setup
p - boot protocoland then select
2 - dhcp protocol, because bootp (default) does not support dynamic address.
o - boot deviceand then select
1 - boot Ethernet once, then NANDto boot once from the network, and then boot from the nand after that.
xto exit setup, the RB450G will reboot. Let the bootloader menu time out, and it should get an address via DHCP and then load the netboot image from your desktop computer. After a minute or so, you should be able to hit <enter> and get to the OpenWRT prompt.
vi /etc/resolv.conf). Replace 127.0.0.1 with 126.96.36.199 or any other public dns server.
rm /etc/resolv.conf; echo nameserver 188.8.131.52 > /etc/resolv.confwill do it.
/etc/init.d/network restartso all configuration changes are reloaded and applied;
ping openwrt.organd see if it works;
/etc/config/networkto your needs and remember to
/etc/init.d/network restartafter you make any changes;
sed -i 's/openwrt-ar71xx-mikrotik-rootfs.tar.gz/openwrt-ar71xx-mikrotik-DefaultNoWifi-rootfs.tar.gz/g' $(which wget2nand)will do it.
wget2nandscript to install OpenWRT into the flash of the RB450G:
wget2nandfinishes, you can reboot the router. This time, the router should boot from flash (since we chose try ethernet once and then nand) and give you a working OpenWRT installation that you can configure as you like.
|System-On-Chip:||Atheros (AR7161) MIPS 24K|
|CPU Speed:||680Mhz (Max 800Mhz)|
|Flash-Chip:||Hynix NAND 512MiB 3,3V 8-bit (HY27UF082G2A, HY27UT084G2A) or Samsung 4Gibit (K9F4G08U0B-PIB0)|
|Flash size:||512 MiB|
|RAM:||256 MiB DDR|
|Boot Flash:||PMC Pm25LV512 512Kbit 3.0V|
|Wireless:||No extension ports|
|Ethernet ports:||1+4 Gbit|
|Serial:||Yes (Standard RS232)|
|JTAG:||Yes (But no pins)|
Schematic Component layout with naming is in RB450G Quick Guide
RB450G have standard RS232 connector, work with simple null modem cable. Testing with standard port in PC. Connection use 1150008n, with hardware flow control (handshaking).
Serial connection is last resort for bootloare RouterBOOT update with XMODEM Microtik Manual:Bootloader upgrade.
JTag port is present on board, but pins are not soldered and there is no empty to solder in pins holes.
Another product from Microtik RB443 use this JTAG configuration:
CPU JTAG in RB433 includes this 7 pins. 7 6 5 4 3 2 1 TRST TDI TDO TMS X TCK GND
How to connect to JTAG interface, and how to reflash the device with JTAG tools
See port.jtag for more JTAG details.
The MicroSD slot needs the
kmod-mmc-spi kernel module packages. The driver configuration is:
DI_pin 1 DO_pin 3 CLK_pin 4 CS_pin 7. The SD card device will be called
/dev/mmcblk0, with the first partition called
/dev/mmcblk0p1. You will need to format the card from the command line before you can use it. For more information about setting up the card as a permanently-mounted filesystem, the USB storage instructions can be adapted, using
/dev/mmcblk0*as the device names.
Some users of the RB450G state that the MicroSD slot is not designed for regular push/pull operations and microSD cards are now fit there well, plus the microSD slot is on the opposite side of the board and is not accessible in many RB450G enclosures designed originally for older RB450 model (no access hole), so when using an old RB450 enclosure you need to fully disassemble the unit to fix / add / remove the microSD card.
List of microSD cards know to work on RB450G with original Microtik RouterOS. Note that since RouterOS uses a different kernel version and MMC driver, cards that don't work with RouterOS may work with OpenWRT, and vice versa.
Verify and make a nice table after similar to one in RouterStation Pro
From AR8316 Switch Support forum
The AR7161 has two Ethernet controllers, therefore there are two interfaces, eth0 and eth1. one of these is the wan port, the other is the connection to the CPU port of the switch. The AR8316 provides the physical ports for both controllers, but they are separated internally.
On the RB450G, it looks like this:
+-----------+ +-----------+ | | eth0 | | | +-------+----------5+-Eth1 (POE) | | | | | AR7161 | | AR8316 +-1+-Eth2 | | eth1 | +-4+-Eth3 | +-------+0-------+-3+-Eth4 | | | +-2+-Eth5 +-----------+ +-----------+