[R7800] default vlan config explaination and use (help)

Installing and Using OpenWrt
1

Hi everybody,
I've read the wiki and also some threads but I'm very confused and really I've lot of questions :frowning:
I'm using the @ACwifidude build for netgear R7800.
Actually, LEDE shows me the following:

immagine
immagine940×412 19.9 KB

but I dont understood several things.
It seems I have two VPN, that are the standard for my hardware... right? And how they communicate one another (they have, otherwise how lan packets go out and viceversa)?
And why the only tagged things are CPUs... it means that each cpu of my dual core router is dedicated to one lan? And why each VLAN is connected to one CPU?
What happens if I select "Enable mirroring of..."?
If I add a third VLAN, can I give it different ip? Where? How this third vlan will be connected only with the wan?

Maybe I also need to understand what all of these interfaces are... (this under "lan": under wan they are more called alias, and I have also wan6!)
LAN
immagine

Thanks for any suggestion!

2

Having two VLANs is the default OpenWrt configuration. One is the WAN network (eth 0), one is the LAN network (eth 1). For the r7800 the default is to have one CPU tagged per VLAN. If you have a need to change it from the defaults - just make sure you pay attention to firewall and wireless sections to make sure the networks communicate with each other the way you want. The default is the same as OEM and works for the vast majority of use cases (you have the default settings :sunglasses: )

There are multiple threads talking about maximizing multi processor performance. My build has irqbalance so you get a decent even distribution. I haven’t found a big improvement from tweaking particular interrupts to be one CPU vs the other. The defaults + irqbalance is simple and performs well.

My main router looks like this (wifi turned off):


root@OpenWrt:~# cat /proc/interrupts
           CPU0       CPU1       
 16:   20443465   54952433     GIC-0  18 Edge      gp_timer
 18:         49          4     GIC-0  51 Edge      qcom_rpm_ack
 19:          0          0     GIC-0  53 Edge      qcom_rpm_err
 20:          0          0     GIC-0  54 Edge      qcom_rpm_wakeup
 26:          0          0     GIC-0 241 Level     ahci[29000000.sata]
 27:          0          0     GIC-0 210 Edge      tsens_interrupt
 30:     199060       1931     GIC-0 202 Level     adm_dma
 33:  650679886          0     GIC-0 245 Level     nss
 34:          0   15983943     GIC-0 264 Level     nss_queue1
 35:  615659823          0     GIC-0 246 Level     nss
 36:          0          0     GIC-0 265 Level     nss_queue1
 37:          0          0     GIC-0 130 Level     bam_dma
 38:          0          0     GIC-0 128 Level     bam_dma
 40:          0          0   PCI-MSI   0 Edge      aerdrv
 42:          0          0   PCI-MSI 134217728 Edge      aerdrv
 43:         12          0     GIC-0 184 Level     msm_serial0
 44:          2          0   msmgpio   6 Edge      keys
 45:          2          0   msmgpio  54 Edge      keys
 46:          2          0   msmgpio  65 Edge      keys
 47:          0          0     GIC-0 142 Level     xhci-hcd:usb1
 48:          0          0     GIC-0 237 Level     xhci-hcd:usb3
 49:         42          0   PCI-MSI 524288 Edge      ath10k_pci
 50:         40          0   PCI-MSI 134742016 Edge      ath10k_pci
IPI0:          0          0  CPU wakeup interrupts
IPI1:          0          0  Timer broadcast interrupts
IPI2:    6797002   15683252  Rescheduling interrupts
IPI3:   12206812    1610968  Function call interrupts
IPI4:          0          0  CPU stop interrupts
IPI5:       1551       1421  IRQ work interrupts
IPI6:          0          0  completion interrupts
Err:          0
3

Thanks ACWifidude, I have lot of doubt / things to learn. So, if I selected as Tagged both cpus for both vlans, there are not performance increases?

4

Nope. I wish!