I understand your last question but it's hard me to answer clearly - yes/no . Instead of this let me show you this log: 17/Feb/2023:17:16:21 +0100 1676650581.827 103 100.121.11.70 100.121.11.70 NONE_NONE/500 0 CONNECT scala-module-5515.scratch.lightning.force.com:443 - HIER_NONE/- - 17/Feb/2023:17:16:22 +0100 1676650582.297 0 100.121.11.70 100.121.11.70 NONE_NONE/500 0 CONNECT scala-module-5515.scratch.lightning.force.com:443 - HIER_NONE/- - 17/Feb/2023:17:16:22 +0100 1676650582.893 0 100.121.11.70 100.121.11.70 NONE_NONE/500 0 CONNECT scala-module-5515.scratch.lightning.force.com:443 - HIER_NONE/- - 17/Feb/2023:17:16:23 +0100 1676650583.625 0 100.121.11.70 100.121.11.70 NONE_NONE/500 0 CONNECT scala-module-5515.scratch.lightning.force.com:443 - HIER_NONE/- - 17/Feb/2023:17:16:23 +0100 1676650583.711 0 100.121.11.70 100.121.11.70 NONE_NONE/500 0 CONNECT scala-module-5515.scratch.lightning.force.com:443 - HIER_NONE/- - 17/Feb/2023:17:16:25 +0100 1676650585.073 0 100.121.11.70 100.121.11.70 NONE_NONE/500 0 CONNECT scala-module-5515.scratch.lightning.force.com:443 - HIER_NONE/- - 17/Feb/2023:17:16:25 +0100 1676650585.799 0 100.121.11.70 100.121.11.70 NONE_NONE/500 0 CONNECT scala-module-5515.scratch.lightning.force.com:443 - HIER_NONE/- - 17/Feb/2023:17:16:25 +0100 1676650585.882 0 100.121.11.70 100.121.11.70 NONE_NONE/500 0 CONNECT scala-module-5515.scratch.lightning.force.com:443 - HIER_NONE/- - 17/Feb/2023:17:16:26 +0100 1676650586.258 0 100.121.11.70 100.121.11.70 NONE_NONE/500 0 CONNECT scala-module-5515.scratch.lightning.force.com:443 - HIER_NONE/- - 17/Feb/2023:17:16:26 +0100 1676650586.995 0 100.121.11.70 100.121.11.70 NONE_NONE/500 0 CONNECT scala-module-5515.scratch.lightning.force.com:443 - HIER_NONE/- - 17/Feb/2023:17:16:28 +0100 1676650588.468 0 100.121.11.70 100.121.11.70 NONE_NONE/500 0 CONNECT scala-module-5515.scratch.lightning.force.com:443 - HIER_NONE/- - 17/Feb/2023:17:16:29 +0100 1676650589.159 0 100.121.11.70 100.121.11.70 NONE_NONE/500 0 CONNECT scala-module-5515.scratch.lightning.force.com:443 - HIER_NONE/- - 17/Feb/2023:17:16:29 +0100 1676650589.560 0 100.121.11.70 100.121.11.70 NONE_NONE/500 0 CONNECT scala-module-5515.scratch.lightning.force.com:443 - HIER_NONE/- - 17/Feb/2023:17:16:30 +0100 1676650590.319 0 100.121.11.70 100.121.11.70 NONE_NONE/500 0 CONNECT scala-module-5515.scratch.lightning.force.com:443 - HIER_NONE/- - This is the last resort parent squid and the 100.121.11.70 is our downstream squid (child). I understand it as follows, thanks to connect_retries set to 10 (here we have more than 10 tries) try to connect. I suppose the A/AAAA records should already be in the DNS, but the last resort squid gave up. Maciek pt., 17 lut 2023 o 17:46 Alex Rousskov <rousskov@xxxxxxxxxxxxxxxxxxxxxxx> napisał(a): > > On 2/17/23 09:31, Maciej Leks wrote: > > > We have being facing the 500 error codes in our squids (v5.7) when it > > comes to communicate with Salesforce DNS for ephemeral hosts > > > A cs128-fra.fra.r.salesforce.com. 30s 85.222.154.211 > > A cs128-fra.fra.r.salesforce.com. 30s 160.8.252.83 > > A cs128-fra.fra.r.salesforce.com. 30s 85.222.152.83 > > 30s TTLs will naturally limit the time Squid can cache these IPs for. > > > > From time to time DNS answers only sending SOA record (no A,AAAA records) > > Squid will fail to forward traffic if Squid does not have the > destination IP address cached and its new DNS lookup returns no IPv4 or > IPv6 records. Moreover, I am not 100% sure -- needs checking/testing -- > but Squid might cache that "negative" no-IPs result (see > negative_dns_ttl that defaults to 60 seconds). > > Do all 500 error cases correspond to DNS answers without IPs? In other > words, is there a 500 error case after a DNS answer with IPs (within 29 > seconds from each other)? > > HTH, > > Alex. > P.S. Sorry for not answering your questions below directly. I do not > have the time to document what Squid debugging logs mean, and I > recommend sharing them without analysis (by non-developers). > > > > dig: > > IP address of sagittarius-oatmilk-722.scratch.my.salesforce.com is > > cs128.salesforce.com. > > cs128-fra.salesforce.com. > > cs128-fra.fra.r.salesforce.com. > > 160.8.255.83 > > 160.8.249.83 > > 85.222.154.211 > > Failed to resolve sagittarius-oatmilk-722.scratch.my.salesforce.com > > Failed to resolve sagittarius-oatmilk-722.scratch.my.salesforce.com > > Failed to resolve sagittarius-oatmilk-722.scratch.my.salesforce.com > > Failed to resolve sagittarius-oatmilk-722.scratch.my.salesforce.com > > IP address of sagittarius-oatmilk-722.scratch.my.salesforce.com is > > cs128.salesforce.com. > > cs128-fra.salesforce.com. > > cs128-fra.fra.r.salesforce.com. > > 85.222.154.211 > > 160.8.255.83 > > 160.8.249.83 > > IP address of sagittarius-oatmilk-722.scratch.my.salesforce.com is > > cs128.salesforce.com. > > cs128-fra.salesforce.com. > > cs128-fra.fra.r.salesforce.com. > > 160.8.253.83 > > > > Squid outputs then: > > 16/Feb/2023:13:45:54 +0100 1676551554.420 107 100.113.24.84 > > 100.113.24.84 NONE_NONE/500 0 CONNECT > > canal-trailblazer-1066.scratch.my.salesforce.com:443 - HIER_NONE/- - - > > - "/CN=gitlab-executor-stg.navio-services.opl-gcp.int" > > 16/Feb/2023:13:51:55 +0100 1676551915.973 82 100.113.25.178 > > 100.113.25.178 NONE_NONE/500 0 CONNECT > > pumpkinspice-pisces-6588.scratch.my.salesforce.com:443 - HIER_NONE/- - > > - - "/CN=gitlab-executor-stg.navio-services.opl-gcp.int" > > 16/Feb/2023:13:52:44 +0100 1676551964.285 95 100.113.24.84 > > 100.113.24.84 NONE_NONE/500 0 CONNECT > > trailblazer-builder-1043.scratch.file.force.com:443 - HIER_NONE/- - - > > Mozilla/5.0%20(X11;%20Linux%20x86_64)%20AppleWebKit/537.36%20(KHTML,%20like%20Gecko)%20HeadlessChrome/109.0.5414.74%20Safari/537.36 > > "/CN=gitlab-executor-stg.navio-services.opl-gcp.int" > > 16/Feb/2023:13:56:11 +0100 1676552171.392 43 100.121.10.183 > > 100.121.10.183 NONE_NONE/500 0 CONNECT > > pistachio-vente-806.scratch.my.salesforce.com:443 - HIER_NONE/- - - - > > "/CN=gitlab-executor-stg.navio-services.opl-gcp.int" > > > > > > Child squids get then (the same situation but different case): > > 17/Feb/2023:13:18:49 +0000 1676639929.989 88 100.121.10.104 > > TCP_TUNNEL/500 0 CONNECT > > beans-goldengate-9524.scratch.my.salesforce.com:443 - > > ANY_OLD_PARENT/100.112.36.14 - > > > > Such a situation but not the same case from squid internals point of > > view I list below: > > 74,5| RequestParser.cc(377) doParse: request-line: retval 1: > > line={266, data='CONNECT > > baybridge-module-8155.scratch.my.salesforce.com:443 HTTP/1.1 > > Host: baybridge-module-8155.scratch.my.salesforce.com:443 > > 2023/02/15 15:44:24.223 kid1| 74,5| RequestParser.cc(379) doParse: > > request-line: url: baybridge-module-8155.scratch.my.salesforce.com:443 > > 2023/02/15 15:44:24.223 kid1| 74,5| Parser.cc(192) grabMimeBlock: mime > > header (0-196) {Host: > > baybridge-module-8155.scratch.my.salesforce.com:443 > > CONNECT baybridge-module-8155.scratch.my.salesforce.com:443 HTTP/1.1 > > Host: baybridge-module-8155.scratch.my.salesforce.com:443 > > Host: baybridge-module-8155.scratch.my.salesforce.com:443 > > 2023/02/15 15:44:24.223 kid1| 23,3| Uri.cc(441) parse: Split URL > > 'baybridge-module-8155.scratch.my.salesforce.com:443' into proto='', > > host='baybridge-module-8155.scratch.my.salesforce.com', port='443', > > path='' > > 2023/02/15 15:44:24.223 kid1| 14,3| Address.cc(389) lookupHostIP: > > Given Non-IP 'baybridge-module-8155.scratch.my.salesforce.com': Name > > or service not known > > 2023/02/15 15:44:24.223 kid1| 33,5| Http1Server.cc(193) > > buildHttpRequest: normalize 1 Host header using > > baybridge-module-8155.scratch.my.salesforce.com:443 > > 2023/02/15 15:44:24.224 kid1| 85,3| client_side_request.cc(637) > > hostHeaderVerify: validate > > host=baybridge-module-8155.scratch.my.salesforce.com, port=443, > > portStr=443 > > 2023/02/15 15:44:24.224 kid1| 14,3| ipcache.cc(722) > > ipcache_gethostbyname: ipcache_gethostbyname: > > 'baybridge-module-8155.scratch.my.salesforce.com', flags=1 > > 2023/02/15 15:44:24.224 kid1| 14,3| ipcache.cc(310) ipcacheRelease: > > ipcacheRelease: Releasing entry for > > 'baybridge-module-8155.scratch.my.salesforce.com' > > 2023/02/15 15:44:24.224 kid1| 14,3| Address.cc(389) lookupHostIP: > > Given Non-IP 'baybridge-module-8155.scratch.my.salesforce.com': Name > > or service not known > > 2023/02/15 15:44:24.224 kid1| 14,4| ipcache.cc(600) > > ipcache_nbgethostbyname: > > baybridge-module-8155.scratch.my.salesforce.com > > 2023/02/15 15:44:24.224 kid1| 14,3| Address.cc(389) lookupHostIP: > > Given Non-IP 'baybridge-module-8155.scratch.my.salesforce.com': Name > > or service not known > > 2023/02/15 15:44:24.224 kid1| 14,5| ipcache.cc(660) > > ipcache_nbgethostbyname_: ipcache_nbgethostbyname: MISS for > > 'baybridge-module-8155.scratch.my.salesforce.com' > > 2023/02/15 15:44:24.224 kid1| 78,3| dns_internal.cc(1788) idnsALookup: > > idnsALookup: buf is 65 bytes for > > baybridge-module-8155.scratch.my.salesforce.com, id = 0x9c4 > > 2023/02/15 15:44:24.224 kid1| 78,3| dns_internal.cc(1724) > > idnsSendSlaveAAAAQuery: buf is 65 bytes for > > baybridge-module-8155.scratch.my.salesforce.com, id = 0x5b5e > > 2023/02/15 15:44:24.224 kid1| 28,3| DestinationIp.cc(78) match: can't > > yet compare 'to_localhost' ACL for > > baybridge-module-8155.scratch.my.salesforce.com > > 2023/02/15 15:44:24.224 kid1| 14,4| ipcache.cc(600) > > ipcache_nbgethostbyname: > > baybridge-module-8155.scratch.my.salesforce.com > > 2023/02/15 15:44:24.224 kid1| 14,3| Address.cc(389) lookupHostIP: > > Given Non-IP 'baybridge-module-8155.scratch.my.salesforce.com': Name > > or service not known > > 2023/02/15 15:44:24.224 kid1| 14,5| ipcache.cc(660) > > ipcache_nbgethostbyname_: ipcache_nbgethostbyname: MISS for > > 'baybridge-module-8155.scratch.my.salesforce.com' > > 2023/02/15 15:44:24.247 kid1| 14,3| ipcache.cc(456) latestError: DNS > > error while resolving baybridge-module-8155.scratch.my.salesforce.com: > > No DNS records > > 2023/02/15 15:44:24.248 kid1| 14,3| ipcache.cc(456) latestError: DNS > > error while resolving baybridge-module-8155.scratch.my.salesforce.com: > > No DNS records > > 2023/02/15 15:44:24.282 kid1| 14,3| ipcache.cc(477) ipcacheParse: 3 > > answers for baybridge-module-8155.scratch.my.salesforce.com > > 2023/02/15 15:44:24.282 kid1| 14,3| ipcache.cc(576) > > ipcacheHandleReply: done with > > baybridge-module-8155.scratch.my.salesforce.com: [no cached IPs] > > 2023/02/15 15:44:24.282 kid1| 14,3| ipcache.cc(477) ipcacheParse: 3 > > answers for baybridge-module-8155.scratch.my.salesforce.com > > 2023/02/15 15:44:24.282 kid1| 14,3| ipcache.cc(576) > > ipcacheHandleReply: done with > > baybridge-module-8155.scratch.my.salesforce.com: [no cached IPs] > > 2023/02/15 15:44:24.282 kid1| 14,3| ipcache.cc(310) ipcacheRelease: > > ipcacheRelease: Releasing entry for > > 'baybridge-module-8155.scratch.my.salesforce.com' > > 2023/02/15 15:44:24.282 kid1| 14,3| ipcache.cc(722) > > ipcache_gethostbyname: ipcache_gethostbyname: > > 'baybridge-module-8155.scratch.my.salesforce.com', flags=1 > > 2023/02/15 15:44:24.282 kid1| 28,3| DomainData.cc(110) match: > > aclMatchDomainList: checking > > 'baybridge-module-8155.scratch.my.salesforce.com' > > 2023/02/15 15:44:24.282 kid1| 28,3| DomainData.cc(115) match: > > aclMatchDomainList: 'baybridge-module-8155.scratch.my.salesforce.com' > > NOT found > > 2023/02/15 15:44:24.283 kid1| 28,3| DomainData.cc(110) match: > > aclMatchDomainList: checking > > 'baybridge-module-8155.scratch.my.salesforce.com' > > 2023/02/15 15:44:24.283 kid1| 28,3| DomainData.cc(115) match: > > aclMatchDomainList: 'baybridge-module-8155.scratch.my.salesforce.com' > > found > > 2023/02/15 15:44:24.283 kid1| 85,2| client_side_request.cc(745) > > clientAccessCheckDone: The request CONNECT > > baybridge-module-8155.scratch.my.salesforce.com:443 is ALLOWED; last > > ACL checked: gitlab-executor-stg-dst > > 2023/02/15 15:44:24.284 kid1| 85,2| client_side_request.cc(745) > > clientAccessCheckDone: The request CONNECT > > baybridge-module-8155.scratch.my.salesforce.com:443 is ALLOWED; last > > ACL checked: gitlab-executor-stg-dst > > 2023/02/15 15:44:24.284 kid1| 85,4| client_side_request.cc(1514) > > processRequest: CONNECT > > baybridge-module-8155.scratch.my.salesforce.com:443 > > 2023/02/15 15:44:24.284 kid1| 26,3| tunnel.cc(1140) tunnelStart: > > CONNECT baybridge-module-8155.scratch.my.salesforce.com:443 HTTP/1.1 > > 2023/02/15 15:44:24.284 kid1| 44,3| peer_select.cc(612) selectMore: > > CONNECT baybridge-module-8155.scratch.my.salesforce.com > > 2023/02/15 15:44:24.284 kid1| 44,3| peer_select.cc(1098) addSelection: > > adding HIER_DIRECT#baybridge-module-8155.scratch.my.salesforce.com > > 2023/02/15 15:44:24.284 kid1| 44,2| peer_select.cc(460) > > resolveSelected: Find IP destination for: > > baybridge-module-8155.scratch.my.salesforce.com:443' via > > baybridge-module-8155.scratch.my.salesforce.com > > 2023/02/15 15:44:24.284 kid1| 14,4| ipcache.cc(607) nbgethostbyname: > > baybridge-module-8155.scratch.my.salesforce.com > > 2023/02/15 15:44:24.284 kid1| 14,3| Address.cc(389) lookupHostIP: > > Given Non-IP 'baybridge-module-8155.scratch.my.salesforce.com': Name > > or service not known > > 2023/02/15 15:44:24.284 kid1| 14,4| ipcache.cc(647) > > ipcache_nbgethostbyname_: ipcache_nbgethostbyname: HIT for > > 'baybridge-module-8155.scratch.my.salesforce.com' > > 2023/02/15 15:44:24.284 kid1| 44,2| peer_select.cc(479) > > resolveSelected: PeerSelector4664913 found all 0 destinations for > > baybridge-module-8155.scratch.my.salesforce.com:443 > > 2023/02/15 15:44:24.284 kid1| 4,3| errorpage.cc(1249) > > compileLegacyCode: %U --> > > 'https://baybridge-module-8155.scratch.my.salesforce.com/*' > > 2023/02/15 15:44:24.284 kid1| 4,3| errorpage.cc(1249) > > compileLegacyCode: %U --> > > 'https://baybridge-module-8155.scratch.my.salesforce.com/*' > > 2023/02/15 15:44:24.284 kid1| 4,3| errorpage.cc(1249) > > compileLegacyCode: %W --> > > '?subject=CacheErrorInfo%20-%20ERR_CANNOT_FORWARD&body=CacheHost%3A%20opl-egress-proxy-vm-31vr%0D%0AErrPage%3A%20ERR_CANNOT_FORWARD%0D%0AErr%3A%20%5Bnone%5D%0D%0ATimeStamp%3A%20Wed,%2015%20Feb%202023%2014%3A44%3A24%20GMT%0D%0A%0D%0AClientIP%3A%20100.121.10.148%0D%0A%0D%0AHTTP%20Request%3A%0D%0ACONNECT%20%20HTTP%2F1.1%0AVia%3A%201.1%20gitlab-proxy-6d445dbd8d-mxtqv%20(squid%2F5.7)%0D%0AX-Forwarded-For%3A%20100.113.24.224%0D%0ACache-Control%3A%20max-age%3D259200%0D%0AConnection%3A%20close%0D%0AHost%3A%20baybridge-module-8155.scratch.my.salesforce.com%3A443%0D%0A%0D%0A%0D%0A' > > 2023/02/15 15:44:24.286 kid1| 33,3| client_side_request.cc(272) > > ~ClientHttpRequest: httpRequestFree: > > baybridge-module-8155.scratch.my.salesforce.com:443 > > 2023/02/15 15:44:24.286 kid1| 33,5| client_side.cc(385) logRequest: > > logging half-baked transaction: > > baybridge-module-8155.scratch.my.salesforce.com:443 > > > > Our parent proxy settings for DNS: > > negative_dns_ttl 3 seconds #if we set 1s it behaves the same > > dns_nameservers 8.8.8.8 1.1.1.1 > > > > The question is: > > If you carefully look at the debug log you see: > > a. I(Squid) can't find IP for the name > > b. I've got 3 IPs from DNS > > c. OK, so I've got IP > > d. ...Oh, I cannot find any IP > > e. I can't find any destinations (what's that?) > > f. I'm outputing an error > > > > So, do you think it's ok or there is a bug? > > > > Rgds, > > Maciej Leks > > _______________________________________________ > > squid-users mailing list > > squid-users@xxxxxxxxxxxxxxxxxxxxx > > http://lists.squid-cache.org/listinfo/squid-users > > _______________________________________________ > squid-users mailing list > squid-users@xxxxxxxxxxxxxxxxxxxxx > http://lists.squid-cache.org/listinfo/squid-users _______________________________________________ squid-users mailing list squid-users@xxxxxxxxxxxxxxxxxxxxx http://lists.squid-cache.org/listinfo/squid-users