AC57U: update firmware to 21.02.0 warning

Hi guys!

I'm using OpenWRT 19.07.7 r11306-c4a6851c72 on an Asus RT-AC57U v1 (MediaTEK) and would like to upgrade the firmware to 21.02.0 release.

When I try to do it via GUI, I have this message:


What should I do?

Thanks in advance for the reply!

The message is giving you already instructions:

Please wipe config during upgrade (force required) or reinstall.

"wipe config" means: Do not keep settings.


:!: There is no migration path for targets that switched from swconfig to DSA. In that case, sysupgrade will refuse to proceed with an appropriate error message:
Image version mismatch. image 1.1 device 1.0 Please wipe config during upgrade (force required) or reinstall. Config cannot be migrated from swconfig to DSA Image check failed

See also


Ok, do you think that is it possible to restore a configuration backup after updating to 21.02.0?

No. That's the same as keeping the config, you're just doing it in two steps.
An experienced user may be able to restore parts of a backup manually, but it cannot be restored as a whole.

Take the backup and use it as a reference while reconfiguring by hand.



I've just flashed the new 21.02.0 without keeping the config.

I've only tried to change the router IP to and I always have rollback as result of this first change. It always come back to

Is there anything different from 19.07 release that I have to do to change the router IP?

iirc luci autometically revert if admin losses connection after config change to guard user from blocking oneself: right after router ip change connect to new IP and login so luci registers your presence

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Or click "apply unchecked"

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I've already clicked on "apply unchecked", but nothing happened.

Instead, connecting to the new IP right after router IP changed did the job.

Unfortunately now I'm not able to configure the other network settings (I've manually changed gateway and DNS using as I had in 19.07 settings, but the network always get as gateway and DNS).

fwiw, sounds like a DHCP server issue.

Are you trying to use the Asus as the only main 'router' (with DHCP server), or as a dumb wireless 'Access Point' (without DHCP server. ie. turned OFF) wired to another ISP facing router (with DHCP server)?

Perhaps post the contents of the old /etc/config/network file from 19.07 backup.

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Here's the old /etc/config/network:

config interface 'loopback'
	option ifname 'lo'
	option proto 'static'
	option ipaddr ''
	option netmask ''

config globals 'globals'
	option ula_prefix 'fd09:1e72:7ba4::/48'

config interface 'lan'
	option type 'bridge'
	option proto 'static'
	option netmask ''
	option ip6assign '60'
	option ipaddr ''
	list dns ''
	option gateway ''
	option ifname 'eth0.1 eth0.2'

config device 'lan_eth0_1_dev'
	option name 'eth0.1'
	option macaddr '40:b0:76:98:9b:d4'

config device 'wan_eth0_2_dev'
	option name 'eth0.2'
	option macaddr '40:b0:76:98:9b:d0'

config switch
	option name 'switch0'
	option reset '1'
	option enable_vlan '1'

config switch_vlan
	option device 'switch0'
	option vlan '1'
	option ports '1 2 3 4 6t'

config switch_vlan
	option device 'switch0'
	option vlan '2'
	option ports '0 6t'

No WAN interface.

Looks like Asus is in dumb AP mode, wired to an ISP facing main router?

Did you disable the DHCP server on OpenWrt router, otherwise it is toss of a coin which of the two DHCP servers responds first to any connected device, and it appears the openwrt router may be winning the race every time?
Only the DHCP server on your ISP facing router should be the one serving DHCP IP addresses to your devices, when used with a dumb AP.

OpenWrt wiki

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Yes, I disabled it.

I took the settings from the 19.07 backup and copied it into the 21.02.0.

I'll double check it later and try again.


As pointed out by @Borromini , do NOT try to literally copy contents of old /etc/config/network file from 19.07 to 21.02. It is incompatible.

You should reset the router to clear old settings and manually set it up from beginning using LuCI.

Once you have configured the dumb AP, try connecting LAN port from Asus openwrt device to your ISP facing router's LAN port.

fwiw, if you are just using the Asus as a dumb AP, have you considered using stock AsusWrt firmware in Access Point mode? AsusWrt offers faster wifi transfer speeds than OpenWrt on RT-AC57u v1 in my experience.

That is exactly why you got that big fat warning when trying to upgrade. And yet here you are, copying old settings, something you were advised not to do.

Your device is on DSA now. Your old /etc/config/networksettings are useless.

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I explained it in a wrong way.

I just used the same settings, not copying files or uploading backups.

Example: my old IP was, so I used the same in the new firmware. The same for DNS and gateway, but unfortunately these two settings weren't working.

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Ok, the problem was that into the br-lan device there wasn't the bridge to wan.

Yes, I use it as DUMB AP.

I also sometimes used 19.02 with Wireguard and configured 5ghz to be not under VPN. I have that backup from 19.02. I will try to manually configure via GUI the 21.02.0 with the same settings.

Ok, I was able to do the same configuration I used for Wireguard in 19.07 straight to the 21.02.0 fw.

The only thing I can't do anymore is use 5ghz wifi without VPN.

As @bill888 told me in an old post for the HH5A (and I used this option for Asus, too), I can do it simply bridging the wireless 5ghz to WAN instead of LAN:


Now for example my smartphone is stuck on "IP acquiring" and can't go over.

Unfortunately, I don't currently have any devices using DSA.

The image you posted is from my openvpn guide for HH5a running 19.07. (DSA is not available for HH5a in 21.02)

For my curiosity, can you provide an image of what is shown in LuCI in 21.02 ?

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Here's a picture of the same section (I guess) in 21.02:

What happens when you click on the list box button?

Also having both WAN and LAN listed does not look correct?
Remove the LAN in first instance if you wish to bridge existing wifi to WAN interface only.

Fwiw, this is from my test EA6350v3 (non-DSA 21.02.0-rc3 device):

I just unticked LAN and selected WAN...