I suspected the relative directory and then noticed the double equal in the prometheus command line. So I erased the old snapshot and tried again.
sysop@r26data0:/var/lib/prometheus/snapshots$ ls sysop@r26data0:/var/lib/prometheus/snapshots$ curl -X POST http: //localhost:30909/api/v1/admin/tsdb/snapshot {"status":"success","data":{"name":"20200707T015331Z-b7fbfbcafd915bb"}} sysop@r26data0:/var/lib/prometheus/snapshots$ sysop@r26data0:/var/lib/prometheus/snapshots$ ls -la total 12 drwxr-xr-x 3 nobody nogroup 4096 Jul 7 01:53 . drwxr-xr-x 14 nobody 65533 4096 Jul 7 00:59 .. drwxr-xr-x 12 nobody nogroup 4096 Jul 7 01:53 20200707T015331Z- b7fbfbcafd915bb Next I run the server again. This time it logs messages about finding data blocks. sysop@r26data0:/var/lib/prometheus/snapshots/20200707T015331Z-b7fbfbcafd915bb$ sudo -u nobody ~/prometheus --storage.tsdb.path=$PWD --web.enable-admin-api --config.file=$HOME/prom-config/config.yaml level=info ts=2020-07-07T01:57:08.662Z caller=main.go:302 msg="No time or size retention was set so using the default time retention" duration=15d level=info ts=2020-07-07T01:57:08.662Z caller=main.go:337 msg="Starting Prometheus" version="(version=2.19.1, branch=HEAD, revision=eba3fdcbf0d378b66600281903e3aab515732b39)" level=info ts=2020-07-07T01:57:08.662Z caller=main.go:338 build_context="(go=go1.14.4, user=root@62700b3d0ef9, date=20200618-16:35:26)" level=info ts=2020-07-07T01:57:08.662Z caller=main.go:339 host_details="(Linux 4.15.0-101-generic #102-Ubuntu SMP Mon May 11 10:07:26 UTC 2020 x86_64 r26data0 (none))" level=info ts=2020-07-07T01:57:08.662Z caller=main.go:340 fd_limits="(soft=65535, hard=65535)" level=info ts=2020-07-07T01:57:08.662Z caller=main.go:341 vm_limits="(soft=unlimited, hard=unlimited)" level=info ts=2020-07-07T01:57:08.664Z caller=main.go:678 msg="Starting TSDB ..." level=info ts=2020-07-07T01:57:08.664Z caller=web.go:524 component=web msg="Start listening for connections" address=0.0.0.0:9090 level=info ts=2020-07-07T01:57:08.664Z caller=repair.go:59 component=tsdb msg="Found healthy block" mint=1594015200000 maxt=1594022400000 ulid= 01ECHNMH8MRPZYHM8KXKBE60ZA level=info ts=2020-07-07T01:57:08.664Z caller=repair.go:59 component=tsdb msg="Found healthy block" mint=1594022400000 maxt=1594029600000 ulid= 01ECHWG8GCAZWMW1JDZB9ERQ0N level=info ts=2020-07-07T01:57:08.664Z caller=repair.go:59 component=tsdb msg="Found healthy block" mint=1594029600000 maxt=1594036800000 ulid= 01ECJ3BZRM3SP7XQAZRJ867C30 level=info ts=2020-07-07T01:57:08.664Z caller=repair.go:59 component=tsdb msg="Found healthy block" mint=1594036800000 maxt=1594044000000 ulid= 01ECJA7Q18RT0VW9S5HKSVDP0J level=info ts=2020-07-07T01:57:08.664Z caller=repair.go:59 component=tsdb msg="Found healthy block" mint=1594044000000 maxt=1594051200000 ulid= 01ECJH3E8ENEWVK8E41G5XWM71 level=info ts=2020-07-07T01:57:08.664Z caller=repair.go:59 component=tsdb msg="Found healthy block" mint=1594051200000 maxt=1594058400000 ulid= 01ECJQZ5GB6TGV21QMHCWZ3JFY level=info ts=2020-07-07T01:57:08.665Z caller=repair.go:59 component=tsdb msg="Found healthy block" mint=1594058400000 maxt=1594065600000 ulid= 01ECJYTWRJZG6YSGH3XBTJK6CX level=info ts=2020-07-07T01:57:08.665Z caller=repair.go:59 component=tsdb msg="Found healthy block" mint=1594065600000 maxt=1594072800000 ulid= 01ECK5PQETDE8VDRSR6NZ6FGXQ level=info ts=2020-07-07T01:57:08.665Z caller=repair.go:59 component=tsdb msg="Found healthy block" mint=1594072800000 maxt=1594080000000 ulid= 01ECKCJEPAJ19AJ7DXJY6K6P6B level=info ts=2020-07-07T01:57:08.665Z caller=repair.go:59 component=tsdb msg="Found healthy block" mint=1594080000000 maxt=1594086829277 ulid= 01ECKFMSZ5XDWD5296R3C8ZXZ6 level=info ts=2020-07-07T01:57:08.688Z caller=head.go:645 component=tsdb msg ="Replaying WAL and on-disk memory mappable chunks if any, this may take a while" level=info ts=2020-07-07T01:57:08.688Z caller=head.go:706 component=tsdb msg ="WAL segment loaded" segment=0 maxSegment=0 level=info ts=2020-07-07T01:57:08.688Z caller=head.go:709 component=tsdb msg ="WAL replay completed" duration=365.54µs level=info ts=2020-07-07T01:57:08.690Z caller=main.go:694 fs_type= EXT4_SUPER_MAGIC level=info ts=2020-07-07T01:57:08.690Z caller=main.go:695 msg="TSDB started" level=info ts=2020-07-07T01:57:08.690Z caller=main.go:799 msg="Loading configuration file" filename=/home/sysop/prom-config/config.yaml level=info ts=2020-07-07T01:57:08.694Z caller=main.go:827 msg="Completed loading of configuration file" filename=/home/sysop/prom-config/config.yaml level=info ts=2020-07-07T01:57:08.694Z caller=main.go:646 msg="Server is ready to receive web requests." The last data block ends about 5 minutes ago. sysop@r26data0:~$ date --date @1594086829 Tue Jul 7 01:53:49 UTC 2020 But still no data. sysop@r26data0:~$ curl http://localhost:9090/api/v1/metadata {"status":"success","data":{}}sysop@r26data0:~$ The web UI shows the following for "/status". Runtime Information Uptime 2020-07-07 01:57:08.663553256 +0000 UTC Working Directory /var/lib/prometheus/snapshots/20200707T015331Z-b7fbfbcafd915bb Configuration reload Successful Last successful configuration reload 2020-07-07 01:57:08 +0000 UTC WAL corruptions 0 Goroutines 32 GOMAXPROCS 8 GOGC GODEBUG Storage Retention 15d Build Information Version 2.19.1 Revision eba3fdcbf0d378b66600281903e3aab515732b39 Branch HEAD BuildUser root@62700b3d0ef9 BuildDate 20200618-16:35:26 GoVersion go1.14.4 Alertmanagers Endpoint Head Stats Number Of Series Number of Chunks Current Max Time Current Min Time 0 0 1594086829277 1594086829277 Total Query Time: 0.000 Seconds Highest Cardinality Labels Name Count Highest Cardinality Metric Names Name Count Label Names With Highest Cumulative Label Value Length Name Length Most Common Label Pairs NameCount -- You received this message because you are subscribed to the Google Groups "Prometheus Users" group. 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