OK, I have a first-seen situation here... I set up BOINC with SETI on a new host of mine that's connected through a UMTS/3G WiFi hotspot. The host has not been able to download any work, have a look at its link. The host is running MS security essentials as antivirus and nothing extra as firewall except from the system defaults.

All tasks fail download with error <error_code>-200 (wrong size)</error_code>, but that error is on ap_601.jpg image file and I've set the BOINC client to skip image file verification, this has been double-checked by examining the global_prefs_override.xml file. Have a look at any unit result Stderr output.

I know the internet provider is compressing images, but why would it not work with image verification set to off? Any hints?

After uninstalling/reinstalling everything BOINC, resetting project and making sure <dont_verify_images> flag was on, I noticed that all downloads started as expected (work units, clients, extra files, images) and nothing was failing until a .jpg was downloaded. At the same time the .jpg download failed, all work units downloads failed as well, which HAD NOT YET STARTED DOWNLOADING. Project client was still downloading as well. All other downloads except from .jpg files finished successfully, including work unit files, only work never started on them. Project folder has now two jpg files on zero bytes.

Any hints or ideas on the matter?

Are the image files compressed to less than 5000 bytes?

BOINC tries to protect itself against misbehaving proxies that don't signal errors properly but instead send some HTML page to the client. If BOINC receives 5000 bytes or less from the server then BOINC assumes that there is a bad proxy between it and the server and truncates the file to zero bytes (=removes the assumed HTML page.)

This doesn't work too well when later on BOINC checks that the file's size and content matches what they were supposed to be.

(Details might be off. It's been a while since this last came up.)

The image files are obviously for the screensaver and not really needed for running the science app but BOINC doesn't know that. It requires that all files for app version are downloaded before it will start processing any tasks marked for that app version. Now if BOINC fails to download some of the app's files it can't start the app so it marks the tasks with download error.

As long as you have <dont_verify_images> set you can download the images with web browser and drop them to the project folder or even simply replace them with any image file. You can find the download links in client_state.xml.

Looks like that's it:

16/04/2014 12:21:42 | SETI@home | Sending scheduler request: To fetch work.
16/04/2014 12:21:42 | SETI@home | Requesting new tasks for CPU
16/04/2014 12:21:43 | SETI@home | Started download of seti_700.jpg
16/04/2014 12:21:43 | SETI@home | Started download of ap_601.jpg
16/04/2014 12:21:45 | SETI@home | Scheduler request completed: got 3 new tasks
16/04/2014 12:21:46 | SETI@home | Incomplete read of 2382.000000 < 5KB for ap_601.jpg - truncating
16/04/2014 12:21:46 | SETI@home | Finished download of ap_601.jpg
16/04/2014 12:21:46 | SETI@home | [error] File ap_601.jpg has wrong size: expected 7653, got 0
16/04/2014 12:21:46 | SETI@home | [error] Checksum or signature error for ap_601.jpg

So your proposal Juha is to place these images manually into the project's folder. I did that a few days ago by myself just in case, but that did not do the trick. I will try again, since it comes from a more proper source...[/code]

Do you think there's any good in my reporting this issue in trac, or should I give up on this host?

Making BOINC accept a file it has not downloaded itself can be a bit tricky at times. BOINC's garbage collector deletes files that BOINC thinks it doesn't need anymore. Your attempt may have been hit by that.

I'm not sure what is the most reliable way to get BOINC accept those files. Is it best to drop the files into project folder before starting BOINC or after starting or maybe both? Whatever is the best way the files need to be in place before BOINC even tries to download them.

It's not entire impossible that the code that checks for file's existance before download ignores the <dont_verify_images> setting.

I would recommend going with minimal cache until you get it working. It's easy to trash your entire daily quota on issues like this.

In case you can't make it work I zipped the images and put them here. The filenames have version numbers but all the Multibeam images and all the Astropulse images are the same so just rename or make new copies as necessary.

As for reporting, your choice.

Perhaps make these pesky files "read only", so that BOINC can't delete them.

Giving up on this host, because all methods proposed in this thread were tested with no positive results.

If you are not Seti-only person you can still make a cruncher out of that host. Just find a project that doesn't have images or where the images are larger than 5000 bytes even when compressed.

I checked in a fix for this problem; it will appear in the next development release.
-- David

---

I did not enter any specific proxy-related information. The image compression takes place behind the scenes, the user has no option whatsoever on the matter.

The change David made should still work. It doesn't matter if the proxy is a voluntary one or one forced on the ISP's clients.

Of course, I too believe David's fix should do it; I will report back here as well as on the trac wiki as soon as I get to try out the next development version of the software.

Hello Dave,

Any timeline on the next dev release that I could try out to test the issue?