[exim] Dkim error LONG_LINE

Hi everyone, sometimes in exim logs I see this message: DKIM: signing
failed: LONG_LINE

I attach the whole message:

2021-04-28 08:29:11 1lbiNS-0007nC-I4 <= <> H=(webmail.ferozo.com)
[200.58.110.110] P=esmtpsa X=TLS1.2:ECDHE-RSA-AES256-GCM-SHA384:256 CV=no A=
fixed_login:sergio@??? S=59294 id=
6c8d677d9282a33f55322731d00a0b05@???
2021-04-28 08:29:11 1lbiNS-0007nC-I4 => glopez <GLopez@???>
R=rotate_ip T=ejecuta_script
2021-04-28 08:29:11 1lbiNS-0007nC-I4 [172.17.80.3] SSL verify error:
certificate name mismatch: DN="/CN=*.ferozo.com" H="172.17.80.3"
2021-04-28 08:29:11 1lbiNS-0007nC-I4 DKIM: signing failed: LONG_LINE
2021-04-28 08:29:11 1lbiNS-0007nC-I4 DKIM: message could not be signed, and
dkim_strict is set. Deferring message delivery.
2021-04-28 08:29:11 1lbiNS-0007nC-I4 H=172.17.80.3 [172.17.80.3]: send() to
172.17.80.3 [172.17.80.3] failed: : No such file or directory
2021-04-28 08:29:11 1lbiNS-0007nC-I4 == glopez@??? <
GLopez@???> R=send_to_smarthost T=remote_smtp defer (2): No such
file or directory H=172.17.80.3 [172.17.80.3]: send() to 172.17.80.3
[172.17.80.3] failed:
2021-04-28 08:37:44 1lbiNS-0007nC-I4 [172.17.80.1] SSL verify error:
certificate name mismatch: DN="/CN=*.ferozo.com" H="172.17.80.1"
2021-04-28 08:37:44 1lbiNS-0007nC-I4 DKIM: signing failed: LONG_LINE
2021-04-28 08:37:44 1lbiNS-0007nC-I4 DKIM: message could not be signed, and
dkim_strict is set. Deferring message delivery.
2021-04-28 08:37:44 1lbiNS-0007nC-I4 H=172.17.80.1 [172.17.80.1]: send() to
172.17.80.1 [172.17.80.1] failed: : No such file or directory
2021-04-28 08:37:44 1lbiNS-0007nC-I4 == glopez@??? <
GLopez@???> R=send_to_smarthost T=remote_smtp defer (2): No such
file or directory H=172.17.80.1 [172.17.80.1]: send() to 172.17.80.1
[172.17.80.1] failed:
2021-04-28 08:41:25 1lbiNS-0007nC-I4 [172.17.80.3] SSL verify error:
certificate name mismatch: DN="/CN=*.ferozo.com" H="172.17.80.3"
2021-04-28 08:41:25 1lbiNS-0007nC-I4 DKIM: signing failed: LONG_LINE
2021-04-28 08:41:25 1lbiNS-0007nC-I4 DKIM: message could not be signed, and
dkim_strict is set. Deferring message delivery.
2021-04-28 08:41:25 1lbiNS-0007nC-I4 H=172.17.80.3 [172.17.80.3]:
172.17.80.3 [172.17.80.3]: No such file or directory
2021-04-28 08:41:25 1lbiNS-0007nC-I4 == glopez@??? <
GLopez@???> R=send_to_smarthost T=remote_smtp defer (2): No such
file or directory H=172.17.80.3 [172.17.80.3]: 172.17.80.3 [172.17.80.3]
2021-04-28 08:53:00 1lbiNS-0007nC-I4 [172.17.80.2] SSL verify error:
certificate name mismatch: DN="/CN=*.ferozo.com" H="172.17.80.2"
2021-04-28 08:53:00 1lbiNS-0007nC-I4 DKIM: signing failed: LONG_LINE
2021-04-28 08:53:00 1lbiNS-0007nC-I4 DKIM: message could not be signed, and
dkim_strict is set. Deferring message delivery.
2021-04-28 08:53:00 1lbiNS-0007nC-I4 H=172.17.80.2 [172.17.80.2]: send() to
172.17.80.2 [172.17.80.2] failed: : No such file or directory
2021-04-28 08:53:00 1lbiNS-0007nC-I4 == glopez@??? <
GLopez@???> R=send_to_smarthost T=remote_smtp defer (2): No such
file or directory H=172.17.80.2 [172.17.80.2]: send() to 172.17.80.2
[172.17.80.2] failed:
2021-04-28 08:53:13 1lbiNS-0007nC-I4 DKIM: signing failed: LONG_LINE
2021-04-28 08:53:13 1lbiNS-0007nC-I4 DKIM: message could not be signed, and
dkim_strict is set. Deferring message delivery.
2021-04-28 08:53:13 1lbiNS-0007nC-I4 H=172.17.80.1 [172.17.80.1]: send() to
172.17.80.1 [172.17.80.1] failed: : No such file or directory
2021-04-28 08:53:13 1lbiNS-0007nC-I4 == glopez@??? <
GLopez@???> R=send_to_smarthost T=remote_smtp defer (2): No such
file or directory H=172.17.80.1 [172.17.80.1]: send() to 172.17.80.1
[172.17.80.1] failed:
2021-04-28 09:00:12 1lbiNS-0007nC-I4 == glopez@??? <
GLopez@???> R=send_to_smarthost T=remote_smtp defer (-53): retry
time not reached for any host for 'oppfilm.com.ar'
2021-04-28 09:00:51 1lbiNS-0007nC-I4 DKIM: signing failed: LONG_LINE
2021-04-28 09:00:51 1lbiNS-0007nC-I4 DKIM: message could not be signed, and
dkim_strict is set. Deferring message delivery.
2021-04-28 09:00:51 1lbiNS-0007nC-I4 H=172.17.80.3 [172.17.80.3]: send() to
172.17.80.3 [172.17.80.3] failed: : No such file or directory
2021-04-28 09:00:51 1lbiNS-0007nC-I4 == glopez@??? <
GLopez@???> R=send_to_smarthost T=remote_smtp defer (2): No such
file or directory H=172.17.80.3 [172.17.80.3]: send() to 172.17.80.3
[172.17.80.3] failed:
2021-04-28 09:01:28 1lbiNS-0007nC-I4 == glopez@??? <
GLopez@???> R=send_to_smarthost T=remote_smtp defer (-53): retry
time not reached for any host for 'oppfilm.com.ar'
2021-04-28 09:03:46 1lbiNS-0007nC-I4 DKIM: signing failed: LONG_LINE
2021-04-28 09:03:46 1lbiNS-0007nC-I4 DKIM: message could not be signed, and
dkim_strict is set. Deferring message delivery.
2021-04-28 09:03:46 1lbiNS-0007nC-I4 H=172.17.80.3 [172.17.80.3]: send() to
172.17.80.3 [172.17.80.3] failed: : No such file or directory
2021-04-28 09:03:46 1lbiNS-0007nC-I4 == glopez@??? <
GLopez@???> R=send_to_smarthost T=remote_smtp defer (2): No such
file or directory H=172.17.80.3 [172.17.80.3]: send() to 172.17.80.3
[172.17.80.3] failed:
2021-04-28 09:03:46 1lbiNS-0007nC-I4 DKIM: signing failed: LONG_LINE
2021-04-28 09:03:46 1lbiNS-0007nC-I4 DKIM: message could not be signed, and
dkim_strict is set. Deferring message delivery.
2021-04-28 09:03:46 1lbiNS-0007nC-I4 H=172.17.80.3 [172.17.80.3]: send() to
172.17.80.3 [172.17.80.3] failed: : No such file or directory
2021-04-28 09:03:46 1lbiNS-0007nC-I4 == glopez@??? <
GLopez@???> R=send_to_smarthost T=remote_smtp defer (2): No such
file or directory H=172.17.80.3 [172.17.80.3]: send() to 172.17.80.3
[172.17.80.3] failed:
2021-04-28 09:03:47 1lbiNS-0007nC-I4 [172.17.80.2] SSL verify error:
certificate name mismatch: DN="/CN=*.ferozo.com" H="172.17.80.2"
2021-04-28 09:03:47 1lbiNS-0007nC-I4 DKIM: signing failed: LONG_LINE
2021-04-28 09:03:47 1lbiNS-0007nC-I4 DKIM: message could not be signed, and
dkim_strict is set. Deferring message delivery.
2021-04-28 09:03:47 1lbiNS-0007nC-I4 H=172.17.80.2 [172.17.80.2]: send() to
172.17.80.2 [172.17.80.2] failed: : No such file or directory
2021-04-28 09:03:47 1lbiNS-0007nC-I4 == glopez@??? <
GLopez@???> R=send_to_smarthost T=remote_smtp defer (2): No such
file or directory H=172.17.80.2 [172.17.80.2]: send() to 172.17.80.2
[172.17.80.2] failed:

I investigated this error but found little information.

### Configuration DKIM in exim

# DKIM
DKIM_DOMAIN = ${domain:$authenticated_id}
DKIM_FILE = /opt/exim/dkim/${domain:$authenticated_id}
DKIM_PRIVATE_KEY = ${if exists{DKIM_FILE}{DKIM_FILE}{0}}

remote_smtp:
driver = smtp
headers_remove = x-originating-ip:
headers_add= ${if eq {$sender_host_address}{127.0.0.1}
{X-Originating-IP:$sending_ip_address}{}}
dkim_domain = DKIM_DOMAIN
dkim_private_key = DKIM_PRIVATE_KEY
dkim_selector = mail
dkim_canon = relaxed
dkim_strict = 1

My idea is to use dkim_strict in 1, so that all messages I send are signed.

Any ideas?

Regards,