protonscr

Steamcmd Assertion error on fresh installs

steamopen SteamCMDDistro Family: Ubuntu
ValveSoftware/steam-for-linux#10994 · opened 2024-06-17 by dybdaltech · updated 2026-05-06 · 2 comments · github
Ddybdaltech 2024-06-17 github

Your system information

  • Steam client version (build number or date): 0~20180105-4
  • Distribution (e.g. Ubuntu): Ubuntu 22.04 & 24.04
  • Opted into Steam client beta?: [Yes/No]No
  • Have you checked for system updates?: [Yes/No] Yes
  • Steam Logs: [generate by running this command in a terminal tar -zcvf ~/Desktop/steam-logs.tar.gz ~/.steam/steam/logs]

Please describe your issue in as much detail as possible:

Steamcmd fails to start throwing a KeyValue error, resulting in a fatal error:

[  0%] Checking for available update...
KeyValues Error: LoadFromBuffer: missing {   (current key: '<!doctype') in file manifest [offset: 15]

../tier1/KeyValues.cpp (2925) : Assertion Failed: Error while parsing text KeyValues for resource manifest
[----] Verifying installation...
[  0%] Downloading Update...
[  0%] Checking for available update...
KeyValues Error: LoadFromBuffer: missing {   (current key: '<!doctype') in file manifest [offset: 15]

../tier1/KeyValues.cpp (2925) : Assertion Failed: Error while parsing text KeyValues for resource manifest
[----] !!! Fatal Error: Steamcmd needs to be online to update.   Please confirm your network connection and try again.
threadtools.cpp (3294) : Assertion Failed: Illegal termination of worker thread 'Thread(0x0x56b5b320/0x0xf770ba'

Possible solutions tried

The solutions mentioned in 7667.
Doing the manual installation steps.
Different hypervisors on different machines
Different OS (Ubuntu 22.04 and 24.04)
Checked DNS

Steps for reproducing this issue:

  1. Follow the steps in https://developer.valvesoftware.com/wiki/SteamCMD#Running_SteamCMD to install Steamcmd
  2. run steamcmd
TTTimo 2024-06-27 github

Hello,

We cannot reproduce this. This is very likely a temporary failure, or a configuration problem on your system.

steamcmd is likely trying to download it's update manifest from https://cdn.steamstatic.com/client/steam_cmd_linux and failing, you need to make sure your host can reach this URL (any proxy or firewall configuration you have needs to allow this).

There may be more information in ~/.steam/steam/logs/bootstrap_log.txt

Ffelbinger 2026-05-06 github

Same issue here, ~/.steam/steam/logs/bootstrap_log.txt contains:

[2026-05-06 18:18:50] Startup - updater built Dec 13 2017 05:27:43
[2026-05-06 18:18:50] Checking for update on startup
[2026-05-06 18:18:50] Checking for available update...
[2026-05-06 18:18:50] Download failed: http error 0 (client-download.steampowered.com/client/steam_cmd_linux)
[2026-05-06 18:18:51] Download failed: http error 0 (media.steampowered.com/client/steam_cmd_linux)
[2026-05-06 18:18:51] failed to load manifest from buffer.
[2026-05-06 18:18:51] Failed to load manifest
[2026-05-06 18:18:51] Error: Download failed: http error 0
[2026-05-06 18:18:51] Verifying installation...
[2026-05-06 18:18:51] Performing checksum verification of executable files
[2026-05-06 18:18:51] Unable to read and verify install manifest /home/linuxgsm/.steam/steamcmd/package/steam_cmd_linux.installed
[2026-05-06 18:18:51] Verification complete
[2026-05-06 18:18:51] Downloading Update...
[2026-05-06 18:18:51] Checking for available update...
[2026-05-06 18:18:51] Download failed: http error 0 (client-download.steampowered.com/client/steam_cmd_linux)
[2026-05-06 18:18:51] Download failed: http error 0 (media.steampowered.com/client/steam_cmd_linux)
[2026-05-06 18:18:51] failed to load manifest from buffer.
[2026-05-06 18:18:51] Failed to load manifest
[2026-05-06 18:18:51] Error: Download failed: http error 0
[2026-05-06 18:18:51] Error: Steamcmd needs to be online to update.	 Please confirm your network connection and try again.
[2026-05-06 18:18:51] Shutdown

It's true that the first link is dead, but the second does work

# curl https://client-download.steampowered.com/client/steam_cmd_linux
curl: (6) Could not resolve host: client-download.steampowered.com
# curl https://media.steampowered.com/client/steam_cmd_linux
"linux"
{
	"version"		"1778007485"
	"steamcmd_public_all"
	{
		"file"		"steamcmd_public_all.zip.ea97f8fd711e4ae492274da96e83bf31eb804528"
		"size"		"58573"
		"sha2"		"4aba96098197f772351e794f987e2b36fcb2e49dc1a3c9a215a6f6573102585c"
	}
	"steamcmd_bins_linux"
	{
		"file"		"steamcmd_bins_linux.zip.743e3d6077ad352d0d5f6bc7b4b9396937fb0993"
		"size"		"35199296"
		"sha2"		"cee2a1eec46cd8efcdec222b80ae56198f5442ad39e4530bfd50185137fce8fa"
		"zipvz"		"steamcmd_bins_linux.zip.vz.29f87186c1a72c502f99fd5fd7714b69a8b53bf6_23478102"
		"sha2vz"		"1807045f8e02d37cbc7d2ff3a540a4d3e0300080a659f7c6a02afd846c329a96"
	}
	"steamcmd_siteserverui_linux"
	{
		"file"		"steamcmd_siteserverui_linux.zip.4c3c5c80954889dee9b42f3b1efec12904041c5b"
		"size"		"14425889"
		"sha2"		"e90c601bd51bfad0edd61398451c86e304a6d1e5f46ea90da92df38730d30708"
		"zipvz"		"steamcmd_siteserverui_linux.zip.vz.ae76ac5cd77df1c21b7e744cc74616e3798c5acc_10791814"
		"sha2vz"		"de2256debde546cd884b426a6d75b1d8389aa997e934c523a6c6203e1c1f0302"
	}
	"steamcmd_linux"
	{
		"file"		"steamcmd_linux.zip.f1b4ce4d897342d119613312245e35d30ea27ffa"
		"size"		"3945900"
		"sha2"		"2f2f0496f9bbc643a268ce243231e86e90fdd758c4c03271840a66e1868655f1"
		"zipvz"		"steamcmd_linux.zip.vz.5e87839c007da9055aa8a3444b9bbc88d31cd6c4_3069733"
		"sha2vz"		"f752ac656354941859f7aa76f6412819e9ee5bc105f96c931c86c17ff287112f"
		"IsBootstrapperPackage"		"1"
	}
}
"kvsign2"
{
	"linux"		"877147e452ef30420884f42324b44f48bcf1103b887c18cb49ea0adc05718cffc0c0346c3b9a3f7f26548092bab44c0c9c3f6807e5bd5118e89b7a4eac29d803"
}
"kvsignatures"
{
	"linux"		"91f6479a83cd07240ce1afa6840edcbf51a808fddfb6b46ba4d76b8b8a380dfb0fa77a27989cf6e0173aec6c963b5755128f92553c65f2137c0fb8d9a11eb828233bcc8341385a23d73661b412c3cd33b9c77f8fe81c52757305ea21dd1f534a54a91fb52be588a0a49a23b0e0d4a3d751c1022b7c56c7669ef6c7b6d21c97c9"
}

This might be a temporary issue, but it still occurs

Upstream links