Topic: Installation problems on a Mikrotik Routerboard RB750UPr2

Sorry for the low-level query, but I'm quite stuck...

I've read most of the Mikrotik-related installation tutorials/instructions I could find on the web, and have a fairly good handle on what's supposed to happen, but I'm failing to get the initramfs to boot on the router. I'm using my arch linux laptop as a host, and have built the appropriate initramfs.elf file from the OpenWRT git repo (at least, I hope it's the appropriate one, I've picked the right targets). I run dnsmasq on my laptop, setting it up to assign the router's MAC an IP and to send it the boot image, assign my laptop's ethernet interface an IP address in the 192.168.1.* range, boot router with reset held down, and can see the router requesting an IP, and being sent the initramfs file.

Then... nothing. I continue holding down reset for a while, then let go. I switch the cable from port 1 to one of the other ports, and start pinging 192.168.1.1. I can hear the router making some noises, but it never responds. I thought maybe having DHCP servers running on both machines would create some conflict, so I killed dnsmasq on my laptop and tried again. Then removed the IP address from my laptop's eth0, thinking the router might assign me an IP, and tried again. Same results in all cases.

What else can I do? The router has no serial port and I'm not prepared to break out the soldering iron. Is there any way to get any more diagnostics?

The Mikrotik section of the downloads area for 15.05 doesn't include an initramfs.elf file, so I went back a version and tried using the initramfs I downloaded from there, thinking maybe that was built more "correctly", and it wouldn't matter which version I used for the intermediate boot. Same result.

I don't know what else I can try!

Re: Installation problems on a Mikrotik Routerboard RB750UPr2

Poking around some more, I found the toh:mikrotik:common page in the wiki, which actually seems to have better information than the device-specific pages. I'm now rebooting the router from within RouterOS (instead of holding down the reset button) using the ethernet-once-then-nand option, as well as Boot protocol: DHCP and Force Backup Booter: Checked, which is marked "!IMPORTANT". It might be good to move some of this information into the device-specific pages.

I've turned on more logging for dnsmasq, and here's the whole interaction between dnsmasq and the booting router (my host machine is 192.168.1.5, the router is given 192.168.1.60):

1244678098 available DHCP range: 192.168.1.50 -- 192.168.1.150
1244678098 vendor class: Mips_boot
1244678098 DHCPDISCOVER(enp3s0) e4:8d:8c:dd:27:83
1244678098 tags: known, enp3s0
1244678098 DHCPOFFER(enp3s0) 192.168.1.60 e4:8d:8c:dd:27:83
1244678098 requested options: 1:netmask, 3:router
1244678098 bootfile name: /srv/tftp/openwrt-ar71xx-mikrotik-vmlinux-initramfs.elf
1244678098 server name: boothost
1244678098 next server: 192.168.1.5
1244678098 sent size:  1 option: 53 message-type  2
1244678098 sent size:  4 option: 54 server-identifier  192.168.1.5
1244678098 sent size:  4 option: 51 lease-time  12h
1244678098 sent size:  4 option: 58 T1  6h
1244678098 sent size:  4 option: 59 T2  10h30m
1244678098 sent size:  4 option:  1 netmask  255.255.255.0
1244678098 sent size:  4 option: 28 broadcast  192.168.1.255
1244678098 sent size:  4 option:  3 router  192.168.1.5
1231716188 available DHCP range: 192.168.1.50 -- 192.168.1.150
1231716188 vendor class: Mips_boot
1231716188 DHCPREQUEST(enp3s0) 192.168.1.60 e4:8d:8c:dd:27:83
1231716188 tags: known, enp3s0
1231716188 DHCPACK(enp3s0) 192.168.1.60 e4:8d:8c:dd:27:83
1231716188 requested options: 1:netmask, 3:router
1231716188 bootfile name: /srv/tftp/openwrt-ar71xx-mikrotik-vmlinux-initramfs.elf
1231716188 server name: boothost
1231716188 next server: 192.168.1.5
1231716188 sent size:  1 option: 53 message-type  5
1231716188 sent size:  4 option: 54 server-identifier  192.168.1.5
1231716188 sent size:  4 option: 51 lease-time  12h
1231716188 sent size:  4 option: 58 T1  6h
1231716188 sent size:  4 option: 59 T2  10h30m
1231716188 sent size:  4 option:  1 netmask  255.255.255.0
1231716188 sent size:  4 option: 28 broadcast  192.168.1.255
1231716188 sent size:  4 option:  3 router  192.168.1.5
sent /srv/tftp/openwrt-ar71xx-mikrotik-vmlinux-initramfs.elf to 192.168.1.60
1231716188 available DHCP range: 192.168.1.50 -- 192.168.1.150
1231716188 vendor class: Mips_boot

Does anything look strange about this?

Re: Installation problems on a Mikrotik Routerboard RB750UPr2

I persist!

Watching the tftp interaction with Wireshark, I see the router send "Read Request, File", then my host sends back Option Acknowledgement with the blksize, then the transfer starts.

Each data packet the host sends to the router gets an acknowledgement that reads ETHERNET FRAME CHECK SEQUENCE INCORRECT (interior details all say something like "Frame check sequence: 0x00000000 [incorrect, should be 0xfb1e82ab]"). That happens for 2483 packets, then nothing: just three more ARP request packets from my host to the router. I'm assuming (hoping!) that this means that the initramfs file isn't getting transferred correctly, and the router has nothing to boot from.

Googling seems to indicate this could be some bad interaction with the tftp server, so I'm going to try again using tftp-hpa and dhcpcd, rather than dnsmasq. For the record, these are my full dnsmasq config options:

interface=enp3s0
enable-tftp
tftp-root=/srv/tftp/
dhcp-range=192.168.0.50,192.168.0.150,12h
dhcp-boot=openwrt-ar71xx-mikrotik-vmlinux-initramfs-lzma.elf,boothost,192.168.0.5
dhcp-host=e4:8d:8c:dd:27:83,192.168.0.60
log-queries
dhcp-authoritative
log-dhcp
port=0

Re: Installation problems on a Mikrotik Routerboard RB750UPr2

Hello,

I have been trying to flash the 911-5HnD and got same issue ETHERNET FRAME CHECK SEQUENCE INCORRECT
I have tried your solution and also tried the method mentioned below but still same issue.
http://www.ericconrad.com/2012/05/insta … 750gl.html

Are you able to resolve the same? Please let me know if you find a way to get rid of this issue.