Hello signoz team, Recently upgraded from v0.15 -> v0.20.2. Running via docker-compose. After trying to remove alerts that were behaving weirdly post update via the alert dashboard, signoz crashed and on reboot alertmanager service fails to pass startup with docker-compose up. On the rare chance it does pass, the frontend is mostly broken and displays not found on all pages after trying to mess around with alerts again. I believe this is a problem with how some alerts were updated via v0.19 upgrade script. (Running this script again gives a seg fault now). I am trying to find a way to make the service usable again, I am ok with manually deleting the current alerts if thats the problem but am unsure where they are stored and how to do so. Thanks in advance :). Current version info:

SigNoz version   : v0.20.2
Commit SHA-1     : 84c4668
Commit timestamp : 2023-06-09T08:52:13Z
Branch           : HEAD
Go version       : go1.18.10

Launch logs from alertmanager service:

2023-06-21T05:34:22.453Z        INFO    rules/thresholdRule.go:754      rule:Runner Error   alerts found: 0
2023-06-21T05:34:22.453Z        INFO    rules/thresholdRule.go:309      msg:sending alerts       rule:Runner Error
2023-06-21T05:34:23.629Z        DEBUG   rules/ruleTask.go:297   msg:%!(EXTRA string=rule task eval started, string=      name:, string=18-groupname, string=     start time:, time.Time=2023-06-21 05:34:23.629831765 +0000 UTC)
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0xfa9cc1]

goroutine 429 [running]:
<http://go.signoz.io/signoz/pkg/query-service/app/queryBuilder.expressionToQuery(0xc000fbe630|go.signoz.io/signoz/pkg/query-service/app/queryBuilder.expressionToQuery(0xc000fbe630>, 0x5?, 0x0)
        /go/src/github.com/signoz/signoz/pkg/query-service/app/queryBuilder/query_builder.go:82 +0x41
<http://go.signoz.io/signoz/pkg/query-service/app/queryBuilder.(*QueryBuilder).PrepareQueries(0xc0004e4dc8|go.signoz.io/signoz/pkg/query-service/app/queryBuilder.(*QueryBuilder).PrepareQueries(0xc0004e4dc8>, 0xc000fbe630, {0x0, 0x0, 0x0?})
        /go/src/github.com/signoz/signoz/pkg/query-service/app/queryBuilder/query_builder.go:178 +0x5d3
<http://go.signoz.io/signoz/pkg/query-service/rules.(*ThresholdRule).prepareBuilderQueries(0xc0004402d0|go.signoz.io/signoz/pkg/query-service/rules.(*ThresholdRule).prepareBuilderQueries(0xc0004402d0>, {0x1916378?, 0xc000fbe2d0?, 0x0?})
        /go/src/github.com/signoz/signoz/pkg/query-service/rules/thresholdRule.go:554 +0x45
<http://go.signoz.io/signoz/pkg/query-service/rules.(*ThresholdRule).buildAndRunQuery(0xc0004402d0|go.signoz.io/signoz/pkg/query-service/rules.(*ThresholdRule).buildAndRunQuery(0xc0004402d0>, {0x1916378, 0xc000fbe5d0}, {0xc0008e75f0?, 0x4588e9?, 0x0?}, {0x191f050, 0xc000ffe2c0})
        /go/src/github.com/signoz/signoz/pkg/query-service/rules/thresholdRule.go:615 +0x11f
<http://go.signoz.io/signoz/pkg/query-service/rules.(*ThresholdRule).Eval(0xc0004402d0|go.signoz.io/signoz/pkg/query-service/rules.(*ThresholdRule).Eval(0xc0004402d0>, {0x1916378, 0xc000fbe5d0}, {0x1318460?, 0xc00079ec90?, 0x0?}, 0x0?)
        /go/src/github.com/signoz/signoz/pkg/query-service/rules/thresholdRule.go:669 +0x97
<http://go.signoz.io/signoz/pkg/query-service/rules.(*RuleTask).Eval.func1({0x1916378|go.signoz.io/signoz/pkg/query-service/rules.(*RuleTask).Eval.func1({0x1916378>?, 0xc000fbe5a0?}, {0x0?, 0xc00069e3d0?, 0x0?}, 0xc0000418c0, 0x4?, {0x1923620, 0xc0004402d0})
        /go/src/github.com/signoz/signoz/pkg/query-service/rules/ruleTask.go:321 +0x22f
<http://go.signoz.io/signoz/pkg/query-service/rules.(*RuleTask).Eval(0xc0000418c0|go.signoz.io/signoz/pkg/query-service/rules.(*RuleTask).Eval(0xc0000418c0>, {0x1916378, 0xc000fbe5a0}, {0xc000794da0?, 0x46a6b9?, 0x0?})
        /go/src/github.com/signoz/signoz/pkg/query-service/rules/ruleTask.go:338 +0x24a
<http://go.signoz.io/signoz/pkg/query-service/rules.(*RuleTask).Run.func1()|go.signoz.io/signoz/pkg/query-service/rules.(*RuleTask).Run.func1()>
        /go/src/github.com/signoz/signoz/pkg/query-service/rules/ruleTask.go:114 +0x87
<http://go.signoz.io/signoz/pkg/query-service/rules.(*RuleTask).Run|go.signoz.io/signoz/pkg/query-service/rules.(*RuleTask).Run>(0xc0000418c0, {0x1916308, 0xc000048018})
        /go/src/github.com/signoz/signoz/pkg/query-service/rules/ruleTask.go:127 +0x4a9
<http://go.signoz.io/signoz/pkg/query-service/rules.(*Manager).addTask.func1()|go.signoz.io/signoz/pkg/query-service/rules.(*Manager).addTask.func1()>
        /go/src/github.com/signoz/signoz/pkg/query-service/rules/manager.go:482 +0x5a
created by <http://go.signoz.io/signoz/pkg/query-service/rules.(*Manager).addTask|go.signoz.io/signoz/pkg/query-service/rules.(*Manager).addTask>
        /go/src/github.com/signoz/signoz/pkg/query-service/rules/manager.go:477 +0x425
2023-06-21T05:34:24.438Z        INFO    version/version.go:43

Since you are running in docker, they will be in sqlite file localted in

deploy/docker/clickhouse-setup/data/signoz/signoz.db

. You can use sqlite tool to remove the alrets.

ty, worked like a charm! On a side note, there may be an unhandled edge case with v0.19 upgrade scripts for some alert rules, not sure if anyone else ran into this issue

You are the first one to run into this issue. Many users had successfully migrated.