# Error connecting to API server

**URL:** <https://kopia.discourse.group/t/error-connecting-to-api-server/2422>\
**Category:** Support\
**Created:** [November 15, 2023, 5:40am UTC](https://kopia.discourse.group/t/error-connecting-to-api-server/2422 "2023-11-15T05:40:48Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![junglebell](https://avatars.discourse-cdn.com/v4/letter/j/87869e/32.png) [@junglebell](https://kopia.discourse.group/u/junglebell)\
**Post date:** [November 15, 2023, 5:40am UTC](https://kopia.discourse.group/t/error-connecting-to-api-server/2422/1 "2023-11-15T05:40:48Z")

</div>

I’m new to Kopia.  
Trying to setup a repo server on a home server to backup family laptops.  
Successfully created repository, added users, and started server as:

```auto
kopia server start \
  --tls-generate-cert \
  --tls-cert-file ~/my.cert \
  --tls-key-file ~/my.key \
  --address="http://0.0.0.0:51515" \
  --server-username=ABC \
  --server-password=ABC

```

I get an error when I try to connect to server from my laptop (on the same LAN):

```auto
$ kopia repository connect server --url=https://192.168.X.Y:51515 --override-username=user --override-hostname=host
Connecting to server 'https://192.168.X.Y:51515' as 'user@host'...
Enter password to open repository: 

ERROR failed to open repository: unable to establish session for purpose=: error establishing session: Session(): rpc error: code = Unavailable desc = connection error: desc = "transport: authentication handshake failed: tls: failed to verify certificate: x509: certificate is valid for 127.0.0.1, not 192.168.X.Y"

```

What could I do to fix this? Please help.

---

<div class="post-metadata">

**Author:** ![kapitainsky](https://yyz2.discourse-cdn.com/free1/user_avatar/kopia.discourse.group/kapitainsky/32/535_2.png) [@kapitainsky](https://kopia.discourse.group/u/kapitainsky)\
**Post date:** [November 15, 2023, 5:48am UTC](https://kopia.discourse.group/t/error-connecting-to-api-server/2422/2 "2023-11-15T05:48:09Z")

</div>

Cert is generated by default for 127.0.0.1 host as per [docs](https://kopia.io/docs/reference/command-line/common/server-start/):

```auto
--tls-generate-cert-name 127.0.0.1 [ADV] Host names/IP addresses to generate TLS certificate for

```

and you connect to 192.168.X.Y hence the error message:

> [@junglebell](#):
>
> `"transport: authentication handshake failed: tls: failed to verify certificate: x509: certificate is valid for 127.0.0.1, not 192.168.X.Y"`

---

<div class="post-metadata">

**Author:** ![junglebell](https://avatars.discourse-cdn.com/v4/letter/j/87869e/32.png) [@junglebell](https://kopia.discourse.group/u/junglebell)\
**Post date:** [November 15, 2023, 6:08am UTC](https://kopia.discourse.group/t/error-connecting-to-api-server/2422/3 "2023-11-15T06:08:30Z")

</div>

@kapitainsky thanks so much, I added the server IP and that error went away, however I am getting this other error now:

```auto
ERROR error connecting to API server: unable to establish session for purpose=: error establishing session: Session(): rpc error: code = Unavailable desc = connection error: desc = "transport: authentication handshake failed: tls: failed to verify certificate: x509: certificate signed by unknown authority"

```

---

<div class="post-metadata">

**Author:** ![kapitainsky](https://yyz2.discourse-cdn.com/free1/user_avatar/kopia.discourse.group/kapitainsky/32/535_2.png) [@kapitainsky](https://kopia.discourse.group/u/kapitainsky)\
**Post date:** [November 15, 2023, 6:14am UTC](https://kopia.discourse.group/t/error-connecting-to-api-server/2422/4 "2023-11-15T06:14:56Z")

</div>

> **[Repository Server](https://kopia.io/docs/repository-server/)**
>
> Fast and Secure Open-Source Backup Software for Windows, Mac, and Linux

---

<div class="post-metadata">

**Author:** ![AndreyDruz](https://yyz2.discourse-cdn.com/free1/user_avatar/kopia.discourse.group/andreydruz/32/897_2.png) [@AndreyDruz](https://kopia.discourse.group/u/AndreyDruz)\
**Post date:** [January 11, 2024, 10:51pm UTC](https://kopia.discourse.group/t/error-connecting-to-api-server/2422/5 "2024-01-11T22:51:11Z")

</div>

From documentation,

> **[Repository Server](https://kopia.io/docs/repository-server/)**
>
> Fast and Secure Open-Source Backup Software for Windows, Mac, and Linux

```auto
kopia repository connect server --url https://<address>:51515 \
  --server-cert-fingerprint 48537cce585fed39fb26c639eb8ef38143592ba4b4e7677a84a31916398d40f7

```

You need to add server cert fingerprint