It's even worse than that, steamcmd request via DNS SPECIFIALLY an A record to reach it's servers, so even in an env with DNS64 and NAT64 it wouldn't work.......
Would need either to dualstack or setup 464xlat which is a pain...
Here is a tcpdump on my end :
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on ens18, link-type EN10MB (Ethernet), snapshot length 262144 bytes
14:25:20.121714 IP6 <REDACTED>.53347 > dns64.cloudflare-dns.com.domain: 19503+ A? client-download.steampowered.com. (50)
14:25:20.167581 IP6 dns64.cloudflare-dns.com.domain > <REDACTED>.53347: 19503 NXDomain 1/1/0 CNAME update.client.steamcontent.akadns.net. (164)
14:25:20.167988 IP6 <REDACTED>.35579 > dns64.cloudflare-dns.com.domain: 49253+ A? client-download.steampowered.com.gamindustri.fr. (65)
14:25:20.186639 IP6 dns64.cloudflare-dns.com.domain > <REDACTED>.35579: 49253 0/1/0 (119)
14:25:20.220352 IP6 <REDACTED>.50583 > dns64.cloudflare-dns.com.domain: 10283+ PTR? 4.6.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.7.4.0.0.7.4.6.0.6.2.ip6.arpa. (90)
14:25:20.240037 IP6 dns64.cloudflare-dns.com.domain > <REDACTED>.50583: 10283 1/0/0 PTR dns64.cloudflare-dns.com. (128)
14:25:20.240586 IP6 <REDACTED>.43819 > dns64.cloudflare-dns.com.domain: 14726+ PTR? 6.0.0.0.6.7.0.0.4.6.9.6.b.6.3.7.2.0.3.2.4.b.e.2.c.7.6.0.1.0.0.2.ip6.arpa. (90)
14:25:20.258911 IP6 dns64.cloudflare-dns.com.domain > <REDACTED>.43819: 14726 NXDomain 0/1/0 (165)
14:25:20.371874 IP6 <REDACTED>.50078 > dns64.cloudflare-dns.com.domain: 23806+ A? media.steampowered.com. (40)
14:25:20.443441 IP6 dns64.cloudflare-dns.com.domain > <REDACTED>.50078: 23806 4/0/0 CNAME cdn.akamai.steamstatic.com.edgesuite.net., CNAME a1843.b.akamai.net., A 92.123.180.10, A 92.123.180.11 (155)
14:25:20.622931 IP6 <REDACTED>.51906 > dns64.cloudflare-dns.com.domain: 28363+ A? client-download.steampowered.com. (50)
14:25:20.640428 IP6 dns64.cloudflare-dns.com.domain > <REDACTED>.51906: 28363 NXDomain 1/1/0 CNAME update.client.steamcontent.akadns.net. (164)
14:25:20.640805 IP6 <REDACTED>.58240 > dns64.cloudflare-dns.com.domain: 40330+ A? client-download.steampowered.com.gamindustri.fr. (65)
14:25:20.660090 IP6 dns64.cloudflare-dns.com.domain > <REDACTED>.58240: 40330 0/1/0 (119)
Nothing extracted yet.
Your system information
Please describe your issue in as much detail as possible:
SteamCMD cannot start on IPv6 only Server, as there is probably no AAAA DNS-Record on the domain for the update server.
(In Wiki in the manual install there is the server
steamcdn-a.akamaihd.netreferenced which has no AAAA Record)I installed SteamCMD with apt and executed it.
DNS Lookup results in some CNAME records (which dont have AAAA either)
Steps for reproducing this issue:
sudo apt updateandsudo apt upgradesudo apt install steamcmdsteamcmd