# Apps can't connect to database - DNS lookup issue

**URL:** <https://forums.percona.com/t/apps-cant-connect-to-database-dns-lookup-issue/24421>\
**Category:** Percona Operator for PostgreSQL\
**Created:** [August 13, 2023, 6:32pm UTC](https://forums.percona.com/t/apps-cant-connect-to-database-dns-lookup-issue/24421 "2023-08-13T18:32:15Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![Slavisa\_Milojkovic](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/slavisa_milojkovic/32/7097_2.png) [@Slavisa\_Milojkovic](https://forums.percona.com/u/Slavisa_Milojkovic)\
**Post date:** [August 13, 2023, 6:32pm UTC](https://forums.percona.com/t/apps-cant-connect-to-database-dns-lookup-issue/24421/1 "2023-08-13T18:32:15Z")

</div>

## Description:

We had dns failure which was restored and now apps can’t connect to postgres dbs. These are the logs

```auto
2023-08-13 18:26:16.593 UTC [8] WARNING C-0x5646eb355bf0: (nodb)/(nouser)@10.42.125.222:59178 pooler error: SSL required
2023-08-13 18:26:18.222 UTC [8] LOG C-0x5646eb355bf0: netbox/(nouser)@10.42.115.196:35668 closing because: server login has been failing, try again later (server_login_retry) (age=0s)
2023-08-13 18:26:18.222 UTC [8] WARNING C-0x5646eb355bf0: netbox/(nouser)@10.42.115.196:35668 pooler error: server login has been failing, try again later (server_login_retry)
2023-08-13 18:26:26.588 UTC [8] LOG C-0x5646eb355bf0: (nodb)/(nouser)@10.42.125.222:49462 closing because: SSL required (age=0s)
2023-08-13 18:26:26.588 UTC [8] WARNING C-0x5646eb355bf0: (nodb)/(nouser)@10.42.125.222:49462 pooler error: SSL required
2023-08-13 18:26:32.994 UTC [8] LOG stats: 0 xacts/s, 0 queries/s, in 0 B/s, out 0 B/s, xact 0 us, query 0 us, wait 0 us

```

Can I restart the cluster somehow to reset the login certs? Everything worked fine, but now pgbouncer can’t authenticate logins.

## Version:

2.2.0

## Logs:

```auto
2023-08-13 18:26:16.593 UTC [8] WARNING C-0x5646eb355bf0: (nodb)/(nouser)@10.42.125.222:59178 pooler error: SSL required
2023-08-13 18:26:18.222 UTC [8] LOG C-0x5646eb355bf0: netbox/(nouser)@10.42.115.196:35668 closing because: server login has been failing, try again later (server_login_retry) (age=0s)
2023-08-13 18:26:18.222 UTC [8] WARNING C-0x5646eb355bf0: netbox/(nouser)@10.42.115.196:35668 pooler error: server login has been failing, try again later (server_login_retry)
2023-08-13 18:26:26.588 UTC [8] LOG C-0x5646eb355bf0: (nodb)/(nouser)@10.42.125.222:49462 closing because: SSL required (age=0s)
2023-08-13 18:26:26.588 UTC [8] WARNING C-0x5646eb355bf0: (nodb)/(nouser)@10.42.125.222:49462 pooler error: SSL required
2023-08-13 18:26:32.994 UTC [8] LOG stats: 0 xacts/s, 0 queries/s, in 0 B/s, out 0 B/s, xact 0 us, query 0 us, wait 0 us

```

There is also this in logs

```auto
2023-08-13 18:32:58.268 UTC [8] WARNING DNS lookup failed: pg-cluster-pg-db-primary: result=0
2023-08-13 18:32:58.268 UTC [8] LOG S-0x5646eb366d60: netbox/_crunchypgbouncer@(bad-af):0 closing because: server DNS lookup failed (age=0s)

```

but DNS works in the cluster for other pods and applications

---

<div class="post-metadata">

**Author:** ![Slavisa\_Milojkovic](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/slavisa_milojkovic/32/7097_2.png) [@Slavisa\_Milojkovic](https://forums.percona.com/u/Slavisa_Milojkovic)\
**Post date:** [August 13, 2023, 11:27pm UTC](https://forums.percona.com/t/apps-cant-connect-to-database-dns-lookup-issue/24421/2 "2023-08-13T23:27:11Z")

</div>

This is the exact issue I have. FQDM in pgbouncer can be changed for postgres v1, but not sure how to change it in v2? Please help!

> [@Pgbouncer server DNS lookup failed](https://forums.percona.com/t/pgbouncer-server-dns-lookup-failed/19731/5):
>
> Yes, that’s the problem. But how do we edit it directly from the PerconaPGCluster manifest without editing the configmap manualy?

---

<div class="post-metadata">

**Author:** ![Slavisa\_Milojkovic](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/slavisa_milojkovic/32/7097_2.png) [@Slavisa\_Milojkovic](https://forums.percona.com/u/Slavisa_Milojkovic)\
**Post date:** [August 14, 2023, 9:02am UTC](https://forums.percona.com/t/apps-cant-connect-to-database-dns-lookup-issue/24421/3 "2023-08-14T09:02:27Z")

</div>

dns gives response only for FQDM

```auto
bash-4.4$ dig pg-cluster-pg-db-pgbouncer

; <<>> DiG 9.11.36-RedHat-9.11.36-8.el8 <<>> pg-cluster-pg-db-pgbouncer
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 40499
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
; COOKIE: a12e6964752a4752 (echoed)
;; QUESTION SECTION:
;pg-cluster-pg-db-pgbouncer. IN A

;; Query time: 61 msec
;; SERVER: 10.43.0.10#53(10.43.0.10)
;; WHEN: Mon Aug 14 07:34:05 UTC 2023
;; MSG SIZE rcvd: 67

bash-4.4$ dig pg-cluster-pg-db-pgbouncer.percona.svc.cluster.local

; <<>> DiG 9.11.36-RedHat-9.11.36-8.el8 <<>> pg-cluster-pg-db-pgbouncer.percona.svc.cluster.local
;; global options: +cmd
;; Got answer:
;; WARNING: .local is reserved for Multicast DNS
;; You are currently testing what happens when an mDNS query is leaked to DNS
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 14358
;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; WARNING: recursion requested but not available

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
; COOKIE: 7a3ec8287a638307 (echoed)
;; QUESTION SECTION:
;pg-cluster-pg-db-pgbouncer.percona.svc.cluster.local. IN A

;; ANSWER SECTION:
pg-cluster-pg-db-pgbouncer.percona.svc.cluster.local. 30 IN A 10.43.109.10

;; Query time: 1 msec
;; SERVER: 10.43.0.10#53(10.43.0.10)
;; WHEN: Mon Aug 14 07:34:21 UTC 2023
;; MSG SIZE rcvd: 161

```

maybe has something to do with this code

```auto
(https://github.com/percona/percona-postgresql-operator/blob/main/internal/naming/dns.go)

```

---

<div class="post-metadata">

**Author:** ![Slavisa\_Milojkovic](https://sea1.discourse-cdn.com/flex019/user_avatar/forums.percona.com/slavisa_milojkovic/32/7097_2.png) [@Slavisa\_Milojkovic](https://forums.percona.com/u/Slavisa_Milojkovic)\
**Post date:** [August 15, 2023, 8:43am UTC](https://forums.percona.com/t/apps-cant-connect-to-database-dns-lookup-issue/24421/4 "2023-08-15T08:43:27Z")

</div>

If somebody needs this, I solved it with rewrite rule mapping in coredns, but it’s not the real solution for this issue

```auto
(https://coredns.io/2017/05/08/custom-dns-entries-for-kubernetes/)

```