Running phantap on other router models

[s0meguy1]

Just a question, could this be run on the GL-AR750S, which is gigabit? Or something a littler faster, like the MT300N?

[champtar]

Hi @s0meguy1

The idea is that you need all the data to go through the linux bridge (br-phantap) for PhanTap to work.
Many small devices have an integrated switch with 1 port connected to the CPU.
So to make it work you need to configure 2 ports as 2 different VLANs, and put them in the br-phantap bridge (you would have for example eth0.1 and eth0.2).

The limitation is that your device might block tagged traffic (802.1Q), which in most case will be fine (I think most devices don't support double tagging).
Also OpenWrt currently use swconfig for switches, but I think they are slowly switching to DSA, which might help. (good presentation about DSA https://netdevconf.org/2.1/papers/distributed-switch-architecture.pdf)

I have a GL-AR750S, I'll try to have a look today.

[s0meguy1]

Thanks! Let me know, I ordered one on Amazon but if it doesn't work, no worries, I can easily return it, after I do some testing trying to get it to work that is

[champtar]

On a GL-AR750S-EXT

root@OpenWrt:~# swconfig dev switch0 help
switch0: mdio-bus.0(Atheros AR8337), ports: 7 (cpu @ 0), vlans: 128
     --switch
	Attribute 1 (int): enable_vlan (Enable VLAN mode)
	Attribute 2 (none): reset_mibs (Reset all MIB counters)
	Attribute 3 (int): enable_mirror_rx (Enable mirroring of RX packets)
	Attribute 4 (int): enable_mirror_tx (Enable mirroring of TX packets)
	Attribute 5 (int): mirror_monitor_port (Mirror monitor port)
	Attribute 6 (int): mirror_source_port (Mirror source port)
	Attribute 7 (int): arl_age_time (ARL age time (secs))
	Attribute 8 (string): arl_table (Get ARL table)
	Attribute 9 (none): flush_arl_table (Flush ARL table)
	Attribute 10 (int): igmp_snooping (Enable IGMP Snooping)
	Attribute 11 (int): igmp_v3 (Enable IGMPv3 support)
	Attribute 12 (none): apply (Activate changes in the hardware)
	Attribute 13 (none): reset (Reset the switch)
     --vlan
	Attribute 1 (int): vid (VLAN ID (0-4094))
	Attribute 2 (ports): ports (VLAN port mapping)
     --port
	Attribute 1 (none): reset_mib (Reset single port MIB counters)
	Attribute 2 (string): mib (Get port's MIB counters)
	Attribute 3 (int): enable_eee (Enable EEE PHY sleep mode)
	Attribute 4 (none): flush_arl_table (Flush port's ARL table entries)
	Attribute 5 (int): igmp_snooping (Enable port's IGMP Snooping)
	Attribute 6 (int): vlan_prio (Port VLAN default priority (VLAN PCP) (0-7))
	Attribute 7 (int): pvid (Primary VLAN ID)
	Attribute 8 (unknown): link (Get port link information)

So you don't have double tagging, but if you just want to use it on a classic ethernet link without VLAN it works fine

It seems there is an upstream DSA driver for this switch, https://lwn.net/Articles/646595/, so someone with more knowledge than me just need to play with the dts and that should work, and then we would not need double tagging to be able to let through tagged packets

[s0meguy1]

Thats pretty good news. Personally I do not know how big my need is for seeing VLAN traffic is, but I'll play around with it, even though attempting to do this may also be above my pay grade. It comes this weekend but I may not be able to play with it until Monday. Thanks for looking into it!

[s0meguy1]

Ok,

I am not as savvy as I thought when it comes to this. How were you able to install it on the 750s? opkg didn't have it in its repos, so I tried to install generic openwrt on it (here) and it bricked it (I had to use sysupgrade -F -n ./file). I had to reflash the stock back. How did you get it working?

[champtar]

Hi @s0meguy1

Sorry for the delay. GL.iNET include an easy to use recovery mode to flash again the router, maybe I had to use that, I don't remember. See the instructions here https://docs.gl-inet.com/en/2/troubleshooting/debrick/, the only difference is that the default IP of OpenWrt is 192.168.1.1

[s0meguy1]

Yeah was able to unbrick it, I just can't get phantap installed on it. What steps did you take to get phantap running?

[champtar]

What error do you have ? What image did you flash ?

[s0meguy1]

So with a fresh boot onto the AR750S, I do an opkg install phantap phantap-learn, and it cannot find the package. I tried to compile from source, however g++/gcc is not supported by openwrt. So I wasn't able to even follow the basic instructions.

[champtar]

Hi,

Did you do opkg update first ? Are you using the master/snapshot images ? (PhanTap is not in the stable branches for now)

[s0meguy1]

So initially I used the default snapshot, that failed, I did some googling and realized I needed the master, as you said. So I went here (https://downloads.openwrt.org/snapshots/targets/ath79/generic/) and downloaded the master, attempted to flash the device via the web GUI and it gave me an error. So then I ssh'ed into the device and flashed it using the CLI, with the commands:
sysupgrade -F -n ./file.bin
After I ran that, it bricked the device, and I gave up and posted on here

[champtar]

Now that you have the snapshot working (if I understand correctly), have you run opkg update before opkg install ... ?

[s0meguy1]

Yes, I did, however I am unsure if the link I provided was the correct master. Can you confirm that is the master branch (https://downloads.openwrt.org/snapshots/targets/ath79/generic/)?

[champtar]

Looks good to me yes