Problem in installing tcpdump on ASUS RT-AX53U after flashing with OpenWrt

Installing and Using OpenWrt
1

Initial Conditions:

  1. Router (ASUS RT-AX53U) flashed with OpenWRT and LuCi installed.
  2. Same connected to internet behind a proxy server as an Access Point with ethernet.
  3. Radios enabled and end device is successfully able to SSH into it.
  4. Firewall at router disabled.

Aim:
To install tcpdump and other packages on it without having to enter proxy details at the router.

Problem:

  1. Tried to upload the package and install from OpenWRT GUI. Sucessfully installed libcap (dependency of tcpdump) but not able to install tcpdump.
    It throws the following error:
Collected errors: * pkg_hash_check_unresolved: cannot find dependency libpcap for tcpdump * pkg_hash_fetch_best_installation_candidate: Packages for tcpdump found, but incompatible with the architectures configured * opkg_install_cmd: Cannot install package tcpdump.
The *opkg install* command failed with code `255`.
  1. Not able to get the log-in page of the proxy from the end device.
2

It is likely you have installed a snapshot rather than a stable release. I'm basing this on the fact that you made a specific reference to installing LuCI (which is preinstalled on stable release builds), and the error itself:

When you get the message “Cannot satisfy the following dependencies for…” it is most likely because you installed a snapshot version of OpenWrt.
Read here for possible solutions.

Downlaod the sysupgrade version from the firmware selector and install it onto your router. Since you have LuCI, you cna use the web interface to do the upgrade (do not keep settings, just as a precaution in case anything has changed that could affect compatibility).

1 Like
3

Thanks for the reply. I will try to flash it with a more stable version, and try again. Also, I haven't installed the LuCl seperately. But seeing that it is the most recent version, I guess you are probably right.

The details currently:

|Hostname|OpenWrt|
|---|---|
|Model|ASUS RT-AX53U|
|Architecture|MediaTek MT7621 ver:1 eco:3|
|Target Platform|ramips/mt7621|
|Firmware Version|OpenWrt 22.03.3 r20028-43d71ad93e / LuCI openwrt-22.03 branch git-22.361.69894-438c598|

Upon searching for the stable release, I couldn't find that for my router RT-AX53U. Searched for OpenWrt 21.02.5 (Released: Wed, 17 Oct 2022) which is stable but couldn't find the file compatible with my device. Can you suggest me any other release for which I can find the file and flash it to router in order to get out of this problem.

4

There was a link using the firmware selector in my earlier response. Did I misread the model info?

5

No, you didn't misread the model info. The link you sent me is directing me back to the page where I can download the version I have already flashed it with (OpenWrt 22.03.3), which you said can be unstable. In order to get around this problem according to you, I should've installed the old stable version OpenWrt 21.02.5 but I cannot find the file compatible with my device upon searching it. You can also see it here and search for asus_rt-ax53u.
Now, as there are many other releases which I can flash it with. I want a suggestion, as to which release I should download other than these two (OpenWrt 22.03.3, OpenWrt 21.02.5) obviously.

6

Your understanding is inaccurate.

I would suggest:

  • Using the Firmware Selector to make an image with tcpdump included; or
  • Connect the router to the Internet and run:
opkg update
opkg install tcpdump
7

I did not say that the link I provided was unstable. I asserted, apparently incorrectly, that you had installed a snapshot release rather than a stable release version. We see the error you reported from users who have outdated snapshots (because snapshots are built daily, his can happen in as little as 24 hours from the download of the snapshot image from the downloads site)

Since you said (later) that you are running 22.03.3, I do have a follow up question: have you ever upgraded packages on your current install (using opkg upgrade or the LuCI upgrade packages button)?

Let's also see the output of:

ubus call system board
1 Like
8

Worked fine here even on some older snapshot.

opkg update 
root@owrt-ap-rt-ax53u:~# opkg update
Downloading https://downloads.openwrt.org/snapshots/targets/ramips/mt7621/packag                                                                                                                                                             es/Packages.gz
Updated list of available packages in /var/opkg-lists/openwrt_core
Downloading https://downloads.openwrt.org/snapshots/targets/ramips/mt7621/packag                                                                                                                                                             es/Packages.sig
Signature check passed.
Downloading https://downloads.openwrt.org/snapshots/packages/mipsel_24kc/base/Packages.gz
Updated list of available packages in /var/opkg-lists/openwrt_base
Downloading https://downloads.openwrt.org/snapshots/packages/mipsel_24kc/base/Packages.sig
Signature check passed.
Downloading https://downloads.openwrt.org/snapshots/packages/mipsel_24kc/luci/Packages.gz
Updated list of available packages in /var/opkg-lists/openwrt_luci
Downloading https://downloads.openwrt.org/snapshots/packages/mipsel_24kc/luci/Packages.sig
Signature check passed.
Downloading https://downloads.openwrt.org/snapshots/packages/mipsel_24kc/packages/Packages.gz
Updated list of available packages in /var/opkg-lists/openwrt_packages
Downloading https://downloads.openwrt.org/snapshots/packages/mipsel_24kc/packages/Packages.sig
Signature check passed.
Downloading https://downloads.openwrt.org/snapshots/packages/mipsel_24kc/routing/Packages.gz
Updated list of available packages in /var/opkg-lists/openwrt_routing
Downloading https://downloads.openwrt.org/snapshots/packages/mipsel_24kc/routing/Packages.sig
Signature check passed.
opkg install tcpdump 
root@owrt-ap-rt-ax53u:~# opkg install tcpdump
Multiple packages (libgcc1 and libgcc1) providing same name marked HOLD or PREFER. Using latest.
Installing tcpdump (4.99.3-1) to root...
Downloading https://downloads.openwrt.org/snapshots/packages/mipsel_24kc/base/tcpdump_4.99.3-1_mipsel_24kc.ipk
Installing libpcap1 (1.10.3-1) to root...
Downloading https://downloads.openwrt.org/snapshots/packages/mipsel_24kc/base/libpcap1_1.10.3-1_mipsel_24kc.ipk
Configuring libpcap1.
Configuring tcpdump.

You probably installed the wrong libpcap.

1 Like
9

You could use the Firmware Selector to build a custom ROM with tcpdump and its dependencies already included.

  • Go to firmware-selector.openwrt.org.
  • Choose your model. The latest release version is automatically selected, if your model has a release version.
  • Click the arrow next to "customize packages." A list of the standard packages will appear.
  • Add tcpdump and other packages that you want to the end of the list. Specify just the top level name; its dependencies will be automatically included.
  • Request the build and wait until it is finished.
  • Download the sysupgrade file to your PC then install it on the router (using Luci sysupgrade page or scp to /tmp then run sysupgrade.)
10

I used the LuCI upgrade packages button.

11

That is the root of your problem.

Upgrading packages (via the CLI opkg upgrade command or the LuCI Upgrade... button) can result in major problems. It is generally highly discouraged, unless you know what you are doing or if there is specific instruction to do so.

Your best bet at this point is to make a backup (it'll save your config files) and then reset the router to defaults. Once that's done, you can restore your backup and you should be able to install packages normally again.

2 Likes
12

You've failed to mention this step in your first post.

1 Like