Solved High nvram usage

[bennor]

You already agreed with Like the script(s) you use is(are) not a solution:



View attachment 48770

What I don't agree with is posting "manipulated" screenshots misrepresenting the real situation. The real NVRAM situation with your minimum configuration RT-AC68U is 59325/65536 after boot and not 47831/65536. @maxbraketorque was the first one to believe you solved the issue.

@Tech9 You are now shifting my comment(s) to mean something they were not intended to mean or address. Further you are now shifting what I've posted to now claim I'm posting "manipulated" screenshots. As such I'm done with this conversation. I already responded to @maxbraketorque confusion with my bit of a tongue in cheek post/screenshot before you decided to jump in and take issue with my post and screenshot.

 

[maxbraketorque]

What I don't agree with is posting "manipulated" screenshots misrepresenting the real situation. The real NVRAM situation with your minimum configuration RT-AC68U is 59325/65536 after boot and not 47831/65536. @maxbraketorque was the first one to believe you solved the issue.

It was a mistake for me to assume that the low value was due to a hard reset, but at the time, I couldn't think of any other way to get the nvram usage that low because I automatically discount the benefit of script methods that manually remove unused variables (for the reason that Merlin described). However, since bennor has been making recommendations to use the script that removes unused nvram variables, I should have realized that was what he had done to get the low value.

Bottomline though is that I think that I still haven't seen anyone post their nvram usage immediately after a hard reset and basic config. This would be very helpful in determining whether a hard reset is a useful solution. But I think most people are like me and don't want to take the dive into doing a hard reset without some obvious indication that it will be beneficial. I am tempted to buy a used AC68U so I can try.

 

[ColinTaylor]

Bottomline though is that I think that I still haven't seen anyone post their nvram usage immediately after a hard reset and basic config. This would be very helpful in determining whether a hard reset is a useful solution. But I think most people are like me and don't want to take the dive into doing a hard reset without some obvious indication that it will be beneficial. I am tempted to buy a used AC68U so I can try.

Just for you. This is after a hard reset and minimal setup.

 

[maxbraketorque]

Just for you. This is after a hard reset and minimal setup.
View attachment 48792

Awesome! Thanks. That's close to 6000 bytes of free nvram compared to my ~200 bytes with my nearly minimal setup that hasn't been reset in something like 5 years. And I currently don't have anything stored in DHCP reservations or in the device name list. I guess I'll have to prep for a hard reset next time I'm at my AC68U.

 

[bennor]

Bottomline though is that I think that I still haven't seen anyone post their nvram usage immediately after a hard reset and basic config.

Post Edit: As an example. RT-AC68U running Asus stock firmware 3.0.0.4.386_51255:

Used nvram show | awk '{print length(), $0 | "sort -n -r"}' | cut -d"=" -f 1 | head -n 20 to obtain the following information.
Pre factory reset (basic router setup no manual IP addresses):
Size: 51202 bytes (14334 left)
Post factory reset (manual configure to get into GUI):
Size: 48911 bytes (16625 left)

An RT-AC68U running Merlin 386.10 that was hard factory reset with limited basic setup:

And the NVRAM value right after flashing from RT-AC68U Asus 3.0.0.4.386_51255 to Asus-Merlin 386.10, no resets involved just straight flash from one limited basic setup firmware to another.

Note: limited basic setup means configuring the router just enough to get into the GUI to flash the firmware. No VPN. No manual reserved IP's. No extra scripts. No USB drive attached. No other extra configuration.

 

[DirtyFlash]

Post Edit: As an example. RT-AC68U running Asus stock firmware 3.0.0.4.386_51255:

Used nvram show | awk '{print length(), $0 | "sort -n -r"}' | cut -d"=" -f 1 | head -n 20 to obtain the following information.
Pre factory reset (basic router setup no manual IP addresses):
Size: 51202 bytes (14334 left)
Post factory reset (manual configure to get into GUI):
Size: 48911 bytes (16625 left)

An RT-AC68U running Merlin 386.10 that was hard factory reset with limited basic setup:
View attachment 48796

And the NVRAM value right after flashing from RT-AC68U Asus 3.0.0.4.386_51255 to Asus-Merlin 386.10, no resets involved just straight flash from one limited basic setup firmware to another.
View attachment 48798

Note: limited basic setup means configuring the router just enough to get into the GUI to flash the firmware. No VPN. No manual reserved IP's. No extra scripts. No USB drive attached. No other extra configuration.

Very interesting and informative, thank you! How recent is the ASUS firmware version? That's quite a significant NVRAM utilization difference between the OEM firmware and Merlin's.

 

[Tech9]

And the NVRAM value right after flashing from RT-AC68U Asus 3.0.0.4.386_51255 to Asus-Merlin 386.10

I have noticed this NVRAM use increase when flashing Asuswrt to Asuswrt-Merlin with older versions as well.

How recent is the ASUS firmware version?

March 02, 2023. It's actually newer that what's used for 386.10 base (GPL 386_50757).

 

[bennor]

How recent is the ASUS firmware version?

The latest from Asus for the RT-AC68U.

ASUS RT-AC68U Firmware version 3.0.0.4.386.51255
2023/03/02

 

[maxbraketorque]

Post Edit: As an example. RT-AC68U running Asus stock firmware 3.0.0.4.386_51255:

...

An RT-AC68U running Merlin 386.10 that was hard factory reset with limited basic setup:
....

And the NVRAM value right after flashing from RT-AC68U Asus 3.0.0.4.386_51255 to Asus-Merlin 386.10, no resets involved just straight flash from one limited basic setup firmware to another.
....

Note: limited basic setup means configuring the router just enough to get into the GUI to flash the firmware. No VPN. No manual reserved IP's. No extra scripts. No USB drive attached. No other extra configuration.

ok. In the same range as what ColinTaylor showed a bit earlier.

 

[A Purohit]

Just to contribute more datapoints, I have an AC68R running Merlin 386.5_2 (never bothered to go to .7). It's a basic setup otherwise, but I'm running an OVPN server on it, and even while remote connected through the VPN, my NVRAM showed 55200/65536 bytes in the GUI.

 

[Iko]

Just found this thread - my RT-AC68U using v386.10 has been behaving oddly recently and I just checked, I guess this must be why, NVRAM usage appears to be completely full:
NVRAM usage 65535 / 65536 bytes
JFFS 7.94 / 62.75 MB

I have all five OpenVPN clients configured, so that I can swap around using the lovely VPN Director feature. But none of them are actually in use right now. Uptime is just a few minutes old. I have 5 manually assigned DHCP entries, out of 13 active clients. I take it this is the thread to read to figure out why this is happening? Not keen to do a factory wipe if it can be avoided..

Just tried this script; Then checked and found only a tiny change (maybe unrelated):

nvram show | awk '{print length(), $0 | "sort -n -r"}' | cut -d"=" -f 1 | head -n 20 size: 65481 bytes (55 left) 931 nc_setting_conf 699 custom_clientlist 573 rc_support 411 sshd_authkeys 253 vpn_client_cust2 181 dhcp_staticlist 164 subnet_rulelist 131 wl1_chansps 120 qos_rulelist 112 vlan_rulelist 92 1:pa5ga2 92 1:pa5ga1 92 1:pa5ga0 89 vpn_client5_ncp_ciphers 89 vpn_client4_ncp_ciphers 89 vpn_client3_ncp_ciphers 89 vpn_client2_ncp_ciphers 89 vpn_client1_ncp_ciphers 88 vpn_client_ncp_ciphers 88 asus_device_list

 

[Tech9]

Not keen to do a factory wipe if it can be avoided.

If the router already started behaving oddly better do factory reset followed by manual and lighter configuration.

 

[Iko]

If the router already started behaving oddly better do factory reset followed by manual and lighter configuration.

OK thanks, I'll just bite the bullet then

 

[bennor]

NVRAM usage appears to be completely full:
NVRAM usage 65535 / 65536 bytes

You were likely having or seeing the Low NVRAM warning in the Asus-Merlin GUI.

Do a hard factory reset followed by a manual reconfiguration. Do not load or import a saved router CFG file. If low NVRAM is still an issue after manual configuration then look at moving any manual DHCP IP reservations to either a separate file (dnsmasq.conf.add) or use YazDHCP. If low NVRAM continues to be an issue after those two steps, then look to using the various script/code (for example this one, and this one, and this one) methods mentioned both in this thread and the several other resent threads on low NVRAM. Just note that those script/code methods do not typically survive reboot of the RT-AC68U and potentially may cause other issues.

RMerlin explains why this low NVRAM issue is occurring in this post:

Low nvram notification is nothing new, and is becoming increasingly common for that old model as it's running out of nvram space with every new firmware adding new nvram settings. It's part of why Asus is leaving it on the 386 branch most likely, as 388 probably adds even more nvram settings.

This 9 years old model is starting to show its age, with Asus having added lots of new features to it since its initial launch in 2013.

I might have to start considering removing some things from the RT-AC68U to save some nvram space. Reducing the number of OpenVPN clients would be such a thing, as each client consumes around 1 KB of nvram even while not in use.