Installing OpenWrt on the Skydog Router

Hello good people,

I have this skydog router which I wanted to make use of after the closed.
Today I found this link:
I followed it the way I understood it, but did not succeed.

  1. I established a TFTP server on (Laptop LAN)
  2. I put in the initramfs image, called it ap.bin
  3. Connected router's WAN port to my laptop LAN
  4. Held the WPS button while booting router. I picked the image successfully
    I was able to ping the router, but could not access it via web UI. I could ssh into it as root and login.
    At that point I was confused as to what is the next stage so I decided to take a guess - so I downloaded the, put it into the TFTP server, renaming it as ap.bin, then repeating the process to get the router to pick it. It did, but instead changed it's IP to, with an SSID that I could connect to, but this then made the router give me a minimal interface to login to where I could not change anything.

I believe that the people who developed the firmware for this router meant well. We thank them. However, our understanding of the instructions could be stopping us from succeeding in running OpenWRT on this router.

Would someone be willing to guide me on what needs to happen/needs to be done after the 1st step after it fetches ap.bin ( ???

Thanking in advance everyone who takes his time to assist with this effort.

I would assume (the device page isn't really concise) that you need to use sysupgrade to install the OpenWrt sysupgrade image:

sysupgrade -n /tmp/openwrt-19.07.3-ath79-generic-pcs_cr5000-squashfs-sysupgrade.bin

(-n to delete the existing config over the upgrade and to initialize the overlay properly)

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Have both the initramfs and the sysupgrade builds of OpenWrt downloaded to your PC.

TFTP boot the initramfs OpenWrt again like you did the first time.

Use scp to push the sysupgrade image to the RAM disk of OpenWrt running in RAM:
scp openwrt19.07.3etcetc-sysupgrade.bin root@

then continue where @slh said log in with ssh and run sysupgrade. This will reboot and you should then have a permanent installation of OpenWrt in flash ready to configure and use.

Do not TFTP boot the sysupgrade image.

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Thank you very much @mk24 and @slh. I have managed to successfully install OpenWRT on the router.

I forgot to ask if it is okay to delete the /tmp/openwrt-19.07.3-ath79-generic-pcs_cr5000-squashfs-sysupgrade.bin after I've used it.

Hi good people,

Having successfully installed OpenWRT on the former Skydog router, I got so elated and decided now is the time to use it as a VPN endpoint.

The firmware is :

OpenWrt 19.07.3 r11063-85e04e9f46 / LuCI openwrt-19.07 branch git-20.136.49537-fb2f363

I wanted to install a VN client that supports OpenVPN/PPTP/L2TP and so found softether vpn client, which matches exactly what I needed.
However, I am unable to install it because of space limitations on this router. On checking, I see as tmpfs has been allocated all the space that I'd rather have allocated to /, which is where packages are supposed to be installed (/overlay) - at least according to opkg configuration.

Looking at the output of df -h it looks like there is something that is not normal with having 30MB allocated to /tmp and 2MB allocated to /

root@SkydogOpenWrt:/overlay# df -h
Filesystem Size Used Available Use% Mounted on
/dev/root 2.5M 2.5M 0 100% /rom
tmpfs 29.1M 268.0K 28.8M 1% /tmp
/dev/mtdblock5 3.6M 1.7M 2.0M 46% /overlay
overlayfs:/overlay 3.6M 1.7M 2.0M 46% /
tmpfs 512.0K 0 512.0K 0% /dev

Is this something I can change??
How do i change it???

Thanking you in advance.

Tmp is likely on ramdisk, so it is temporary, not flash.

You only have 8 MB flash, based on wiki.
That gets consumed by kernel and roots (rom), and the remaining space is readwrite overlayfs, visible as free space on /

Where is this 29.1MB mounted on /tmp coming from?

And so, you are saying that I cannot install the vpnclient at all??

29.1 is approximately half the size of the RAM (after subtracting about 4 MB that the kernel occupies). This is the default limit on the RAM disk. As others said, /tmp is not suitable for installing software because it is erased and repopulated on every reboot. Also storing large files in /tmp takes away RAM that could be used by applications.

I don't know about softether but I have run VPNs OpenVPN and Zerotier on 8/64 hardware. Not at the same time of course. Also Wireguard is reportedly designed to be light on memory use, but I don't have much experience with it.