Hello everyone.

I'm thinking about replacing the default firmware of UniFi AP AC Lite with OpenWRT, but I wanted to clarify something first.

I wanted to configure two separated wireless networks, each one with a different SSID: one bridged to the physical interface (both sides seeing each other) and a second one NATed to it (wireless clients getting DHCP server info from UAP itself and visible to the external world as a masqueraded address). Is this possible on OpenWRT?

Thanks for the help!

(Last edited by br.larini on 9 Aug 2016, 13:55)

If you have not seen this then maybe this will answer your questions. 
https://wiki.openwrt.org/doc/recipes/guest-wlan?s[]=guest&s[]=lan

You may or may not understand that loading OpenWrt turns your "AP" into a full fledged router.  It is relevant for configuration to know if you plan to use this as a "Router with AP" or as a "dumb AP".  If the later, then the primary router will come into play, as the above link discusses.

Hi, thanks for the reply.
Yes I understand that, but I was uncertain if I could both bridge and NAT the single Ethernet port.
I'll try to do as suggested and post the results. Thanks.

Okay, had some issues but I managed to install OpenWrt (Driver 49876) and configure networking as desired. Everything went just fine after the first step. Here is what I did, in case it helps someone else:

1 - Had to downgrade the OEM firmware, because some new protection that was implemented on newer versions prevents third-party software from being installed. I was on 3.7.5, and according to some research, some people had success using 3.4.7, but Ubiquiti website doesn't have it available anymore. So I found it here: https://jonbither.com/unifi/firmware/U7 … rmware.bin

2 - Installed OpenWrt as told in the wiki page: https://wiki.openwrt.org/toh/ubiquiti/unifiac. ps.: the link to the firmware in the page is broken, so I got it from here: https://downloads.openwrt.org/snapshots … pgrade.bin (for UAP-AC Lite)

3 - Installed Luci following these instructions: https://wiki.openwrt.org/doc/howto/luci.essentials

4 - As the Ethernet and Wireless interfaces were already bridged, I just created and configured a new (guest) wireless interface, enabled DHCP server for it, enabled FORWARD in the Firewall section and set SNAT to source (LAN) IP address.

Now something that I didn't find on Luci or via command line is how (or whether is possible) to enable the 5 GHz band. Here is the output of 'iw phy':

root@OpenWrt:~# iw phy
Wiphy phy0
        max # scan SSIDs: 4
        max scan IEs length: 2257 bytes
        max # sched scan SSIDs: 0
        max # match sets: 0
        Retry short limit: 7
        Retry long limit: 4
        Coverage class: 0 (up to 0m)
        Device supports AP-side u-APSD.
        Device supports T-DLS.
        Available Antennas: TX 0x3 RX 0x3
        Configured Antennas: TX 0x3 RX 0x3
        Supported interface modes:
                 * IBSS
                 * managed
                 * AP
                 * AP/VLAN
                 * WDS
                 * monitor
                 * mesh point
                 * P2P-client
                 * P2P-GO
                 * outside context of a BSS
        Band 1:
                Capabilities: 0x11ee
                        HT20/HT40
                        SM Power Save disabled
                        RX HT20 SGI
                        RX HT40 SGI
                        TX STBC
                        RX STBC 1-stream
                        Max AMSDU length: 3839 bytes
                        DSSS/CCK HT40
                Maximum RX AMPDU length 65535 bytes (exponent: 0x003)
                Minimum RX AMPDU time spacing: 8 usec (0x06)
                HT TX/RX MCS rate indexes supported: 0-15
                Frequencies:
                        * 2412 MHz [1] (20.0 dBm)
                        * 2417 MHz [2] (20.0 dBm)
                        * 2422 MHz [3] (20.0 dBm)
                        * 2427 MHz [4] (20.0 dBm)
                        * 2432 MHz [5] (20.0 dBm)
                        * 2437 MHz [6] (20.0 dBm)
                        * 2442 MHz [7] (20.0 dBm)
                        * 2447 MHz [8] (20.0 dBm)
                        * 2452 MHz [9] (20.0 dBm)
                        * 2457 MHz [10] (20.0 dBm)
                        * 2462 MHz [11] (20.0 dBm)
                        * 2467 MHz [12] (disabled)
                        * 2472 MHz [13] (disabled)
                        * 2484 MHz [14] (disabled)
        valid interface combinations:
                 * #{ managed } <= 2048, #{ AP, mesh point } <= 8, #{ P2P-client, P2P-GO } <= 1, #{ IBSS } <= 1,
                   total <= 2048, #channels <= 1, STA/AP BI must match, radar detect widths: { 20 MHz (no HT), 20 MHz, 40 MHz }

                 * #{ WDS } <= 2048,
                   total <= 2048, #channels <= 1, STA/AP BI must match
        HT Capability overrides:
                 * MCS: ff ff ff ff ff ff ff ff ff ff
                 * maximum A-MSDU length
                 * supported channel width
                 * short GI for 40 MHz
                 * max A-MPDU length exponent
                 * min MPDU start spacing

Can someone help me with that?

Well, I've missed the 5GHz explanation on the AP's wiki topic, so 5GHz is now available after installing ath10k driver:

opkg install kmod-ath10k ath10k-firmware-qca988x

Everything is working as expected now.

Thank you for confirming the updated steps for installing OpenWrt on the UAP-AC-Lite and posting a link for the downgraded firmware. I do find the Ubiquiti Unifi software too restrictive for home use environment and want to try OpenWrt on the AP as well.

Will you share the stability of the AP after flashing with OpenWrt? I have a TP-Link C7 running OpenWrt but I find that I have to reboot it daily to maintain optimal WiFi performance (maybe network throughput as well). I have not had to do it with the UAP-AC-Lite running latest firmware from Ubiquiti yet.

My plan is to use the UAP-AC-Lite 5 GHZ on WDS mode and use 2.4 GHZ in client mode and bridge the two wireless interfaces. This will allow me to use the 5 GHZ band to extend the 2.4 GHZ band. I have successfully tested this on a WD router but will post the results when I try this on the UAP-AC-lite.

(Last edited by rlin78 on 22 Aug 2016, 14:16)

Hi, unfortunately it won't be possible for me to confirm you that. This specific AP device is only on during working hours; the majority of the power lines are turned off during the night (for safety reasons). I also hadn't the opportunity to test the 5GHz bandwidth performance, or several active concurrent downloads to test the throughput even at 2.4Ghz.
I can just confirm it is stable with something around 20~30 simultaneous clients who aren't actively using their devices all the time, and using both bands.
Sorry I couldn't be more helpful.

I plan to put OpenWrt on the UAP this weekend and will report whether I am successful, thanks!

I was able to downgrade to 3.4.7.3284 but cannot get openwrt to install.

I changed the procedure because I didn't setup the scp server. so I used the wget command to download directly from the openwrt download page.

I got as far doing the mtd command but it boots back into ubnt firmware 3.4.7.3284. What am I doing wrong? I see some of the files for openwrt but cannot install LUCI or perform any upgrades. I first copy the file to /tmp by running wget command to download the openwrt firmware. then running the following command

mtd -r write /tmp/openwrt-ar71xx-generic-ubnt-unifiac-squashfs-sysupgrade.bin kernel0
Unlocking kernel0 ...

Writing from /tmp/openwrt-ar71xx-generic-ubnt-unifiac-squashfs-sysupgrade.bin to kernel0 ...
Rebooting ...

It always boots back into 3.4.7.3284

(Last edited by rlin78 on 13 Sep 2016, 02:26)

Not sure what I did wrong. I reloaded the 3.4.7.3284 firmware from a different site and it worked this time.

One thing I want to note is the password is the openwrt username and password: root , no password

So I can confirm that the wget method works and you don't need to do the scp step if you don't have a SCP server.

I have it up and running now, starting to enjoy the freedom and having a web interface. thank you!

(Last edited by rlin78 on 13 Sep 2016, 04:13)

Hello all,

i'm very interested in what br.larini says (configure NAT and dhcp service on the AP).
In particular, if i buy the model with 2 ethernet interfaces (UAP-AC-PRO), would be possible to use them as two separated network interfaces (each with an IP address on different networks), then bridge both the interfaces in as many SSID?
Other question: do you know if the ethernet port supports 802.1Q?
In this way i might buy the LITE model and bring all the necessary VLANs on a trunk link.

Thanks in advance and best regards,

Edoardo

Openwrt supports VLAN tagging, and each SSID can be associated with a different interface and can be assigned a completely different subnet. I am not sure how stable it is and I don't understand why you want to try to do this on an UniFi Access Point because the limited number of ports available. It's also not straight forward to setup OpenWrt on the UAP as you can see.

I would pick up a mid-grade NetGear or TP-Link wireless router that supports OpenWrt for $50-$60. you get all 5 GiG ports, and be ready to spend a few hours setting it up because the way you are asking these questions leads me to believe you have some networking experience, but not on OpenWrt. There's a somewhat big learning curve with OpenWrt for advance networking.

Thank you rlin,
the reason is simple: with the wifi Range declareted by the datasheet, i would be able to cover all the area that i need. Now to achieve this i'm using 3 TP link all with openwrt in WDS mode. They perform enough well, but the hardware is quite dated (two TL-WR841N and a TL-WDR4300) and i would upgrade to AC. In the past i had some good experience with Ubiquiti products, and the cost of a single AP is quite similar (or smaller) to many AC solutions provided by TP, Netgear and so on.

I only have a UAP AC Lite, I can tell you that range is about the same as TP-Link C7 that I have, maybe even slightly worse. The PRO version may be better, but I wouldn't believe everything on the datasheet because it is based on ideal testing conditions.

(Last edited by rlin78 on 16 Nov 2016, 18:43)