There are some issues in your hostname and /etc/hosts configuration. Try followings:

• Always use FQDN format when setting hostname; for example- mail.example.com
• Configure /etc/hosts as instructed in the official documentation. Link

So in short:

hostnamectl set-hostname mail.example.com

# Remove unnecessary things from /etc/hosts
> /etc/hosts

# Add recommended entries to /etc/hosts

cat <<EOF>> /etc/hosts
127.0.0.1  localhost
192.168.0.51   mail.example.com   mail
EOF

# Check /etc/hosts after configuration
cat/ etc/hosts

• Do not leave any ipv6 references in /etc/hosts

Now what causes the issue you encountered, to begin with:

among few things, one of them is when you execute the service-discover setup-wizard it tries to connect to your ldap via resolving your hostname and IP address. And when /etc/hosts are not properly configured, then it fails to resolve. 

Hope it helps.

There are some issues in your hostname and /etc/hosts configuration. Try followings:

• Always use FQDN format when setting hostname; for example- mail.exmaple.com
• Configure /etc/hosts as instructed in the official documentation. Link

So in short:

hostnamectl set-hostname mail.example.com

# Remove unnecessary things from /etc/hosts
> /etc/hosts

# Add recommended entries to /etc/hosts

cat <<EOF>> /etc/hosts
127.0.0.1  localhost
192.168.0.51   mail.example.com   mail
EOF

# Check /etc/hosts after configuration
cat/ etc/hosts

• Do not leave any ipv6 references in /etc/hosts

Now what causes the issue you encountered, to begin with:

among few things, one of them is when you execute the service-discover setup-wizard it tries to connect to your ldap via resolving your hostname and IP address. And when /etc/hosts are not properly configured, then it fails to resolve. 

Hope it helps.

Could you please share the output of followings:

hostname -f && hostname -i && getent hosts $(hostname -f) && cat /etc/hosts

root@justourmail:/etc# service-discover setup-wizard
panic: runtime error: invalid memory address or nil pointer dereference


goroutine 1 :
github.com removed link (*Conn).nextMessageID(...)
removed link
github.com removed link (*Conn).SimpleBind(0x0, 0xc000090fc0)
removed link +0x13f
github.com removed link (*Conn).Bind(0xc0000e04f8?, {0xc0000d5140?, 0x418f94?}, {0xc000166196?, 0x8a1660?})
removed link +0x53
github.com removed link (0xc0000b88a0, 0x25?)
removed link +0x1e8
github.com removed link (*ldapContext).QueryAllServersWithService(0x959329?, {0x94d817, 0x10})
removed link +0x65
github.com removed link (*Setup).isFirstInstance(0xc0000a6aa0, {0x9fd750, 0xc0000aae70})
removed link +0x78
github.com removed link (*Wizard).Run(0xc00011e0b0, 0xc00011e008)
removed link +0x109
reflect.Value.call({0x8c1140?, 0xc00011e0b0?, 0x943b40?}, {0x94591d, 0x4}, {0xc0000a4f18, 0x1, 0x1?})
removed link +0xca6
reflect.Value.Call({0x8c1140?, 0xc00011e0b0?, 0xc000091978?}, {0xc0000a4f18?, 0x943b40?, 0x10?})
removed link +0xb9
github.com removed link ({0x8c1140?, 0xc00011e0b0?, 0xc000091ac8?}, 0xc0001587b0)
removed link +0x45a
github.com removed link (*Context).RunNode(0xc0000fe200, 0xc00012a1e0, {0xc000091ef8, 0x1, 0x90d140?})
removed link +0x7ee
github.com removed link (*Context).Run(0xc0000fe200?, {0xc000091ef8?, 0xc0000a0f08?, 0xc0000a98c0?})
removed link +0x132
main.main()
removed link +0x89

Thanks in advance

Keith