curl: (60) server certificate verification failed. CAfile: /etc/ssl/certs/ca-certificates.crt

curl: (60) server certificate verification failed. CAfile: /etc/ssl/certs/ca-certificates.crt CRLfile: none

1. curl: (60) server certificate verification failed. CAfile: /etc/ssl/certs/ca-certificates.crt CRLfile: none

strong@foreverstrong:~/venv/tensorflow_work/fire-detection-cnn$ bash ./download-models.sh 
Downloading pretrained models...

curl: (60) server certificate verification failed. CAfile: /etc/ssl/certs/ca-certificates.crt CRLfile: none
More details here: http://curl.haxx.se/docs/sslcerts.html

curl performs SSL certificate verification by default, using a "bundle"
 of Certificate Authority (CA) public keys (CA certs). If the default
 bundle file isn't adequate, you can specify an alternate file
 using the --cacert option.
If this HTTPS server uses a certificate signed by a CA represented in
 the bundle, the certificate verification probably failed due to a
 problem with the certificate (it might be expired, or the name might
 not match the domain name in the URL).
If you'd like to turn off curl's verification of the certificate, use
 the -k (or --insecure) option.
strong@foreverstrong:~/venv/tensorflow_work/fire-detection-cnn$

2. reboot

重启系统，然后再次下载。

strong@foreverstrong:~/venv/tensorflow_work/fire-detection-cnn$ bash ./download-models.sh
......

3. export GIT_SSL_NO_VERIFY=1

关闭系统的安全认证，然后再次下载。

export GIT_SSL_NO_VERIFY=1
or
git config --global http.sslverify false

strong@foreverstrong:~/venv/tensorflow_work/fire-detection-cnn$ export GIT_SSL_NO_VERIFY=1
strong@foreverstrong:~/venv/tensorflow_work/fire-detection-cnn$ 
strong@foreverstrong:~/venv/tensorflow_work/fire-detection-cnn$ bash ./download-models.sh
......

4. sudo update-ca-certificates

strong@foreverstrong:~/venv/tensorflow_work/fire-detection-cnn$ sudo update-ca-certificates
[sudo] password for strong: 
Updating certificates in /etc/ssl/certs...
0 added, 0 removed; done.
Running hooks in /etc/ca-certificates/update.d...

done.
done.
strong@foreverstrong:~/venv/tensorflow_work/fire-detection-cnn$ 
strong@foreverstrong:~/venv/tensorflow_work/fire-detection-cnn$ bash ./download-models.sh
......

5. 更新 curl

卸载 sudo apt-get remove curl
安装 sudo apt-get install curl

6. If you’d like to turn off curl’s verification of the certificate, use the -k (or --insecure) option.

################################################################################

# model downloader / unpacker - (c) 2018 Toby Breckon, Durham University, UK

################################################################################

URL_MODELS=https://collections.durham.ac.uk/downloads/r19880vq98m
MODEL_DIR_LOCAL_TARGET=models

MODELS_FILE_NAME=dunnings-2018-fire-detection-pretrained-models.zip
MODELS_DIR_NAME_UNZIPPED=dunnings-2018-fire-detection-pretrained-models
MODELS_MD5_SUM=98815a8594a18f1cafb3e87af8f9b0f1

################################################################################

# set this script to fail on error

set -e

# check for required commands to download and md5 check

(command -v curl | grep curl > /dev/null) ||
  (echo "Error: curl command not found, cannot download!")

(command -v md5sum | grep md5sum > /dev/null) ||
  (echo "Error: md5sum command not found, md5sum check will fail!")

################################################################################

# perform download

echo "Downloading pretrained models..."

mkdir -p $MODEL_DIR_LOCAL_TARGET

MODELS=./$MODEL_DIR_LOCAL_TARGET/$MODELS_FILE_NAME

curl --progress-bar $URL_MODELS > $MODELS -k

################################################################################

# perform md5 check and move to required local target directory

cd $MODEL_DIR_LOCAL_TARGET

echo "checking the MD5 checksum for downloaded models..."

CHECK_SUM_CHECKPOINTS="$MODELS_MD5_SUM  $MODELS_FILE_NAME"

echo $CHECK_SUM_CHECKPOINTS | md5sum -c

echo "Unpacking the zip file..."

unzip -q $MODELS_FILE_NAME

echo "Tidying up..."

mv $MODELS_DIR_NAME_UNZIPPED/* .

rm $MODELS_FILE_NAME && rm -r $MODELS_DIR_NAME_UNZIPPED

cd ..

################################################################################

# tlearn format specific - create checkpoint path files to enable conversion to pb format

echo "model_checkpoint_path: \"firenet\"" > $MODEL_DIR_LOCAL_TARGET/FireNet/checkpoint
echo "all_model_checkpoint_paths: \"firenet\"" >> $MODEL_DIR_LOCAL_TARGET/FireNet/checkpoint

echo "model_checkpoint_path: \"inceptiononv1onfire\"" > $MODEL_DIR_LOCAL_TARGET/InceptionV1-OnFire/checkpoint
echo "all_model_checkpoint_paths: \"inceptiononv1onfire\"" >> $MODEL_DIR_LOCAL_TARGET/InceptionV1-OnFire/checkpoint

echo "model_checkpoint_path: \"sp-inceptionv1onfire\"" > $MODEL_DIR_LOCAL_TARGET/SP-InceptionV1-OnFire/checkpoint
echo "all_model_checkpoint_paths: \"sp-inceptionv1onfire\"" >> $MODEL_DIR_LOCAL_TARGET/SP-InceptionV1-OnFire/checkpoint

################################################################################

echo "... completed -> required models are in $MODEL_DIR_LOCAL_TARGET/"

################################################################################

strong@foreverstrong:~/venv/tensorflow_work/fire-detection-cnn$ bash ./download-models.sh 
Downloading pretrained models...

curl: (60) server certificate verification failed. CAfile: /etc/ssl/certs/ca-certificates.crt CRLfile: none
More details here: http://curl.haxx.se/docs/sslcerts.html

curl performs SSL certificate verification by default, using a "bundle"
 of Certificate Authority (CA) public keys (CA certs). If the default
 bundle file isn't adequate, you can specify an alternate file
 using the --cacert option.
If this HTTPS server uses a certificate signed by a CA represented in
 the bundle, the certificate verification probably failed due to a
 problem with the certificate (it might be expired, or the name might
 not match the domain name in the URL).
If you'd like to turn off curl's verification of the certificate, use
 the -k (or --insecure) option.
strong@foreverstrong:~/venv/tensorflow_work/fire-detection-cnn$ 
strong@foreverstrong:~/venv/tensorflow_work/fire-detection-cnn$ bash ./download-models.sh 
Downloading pretrained models...
######################################################################## 100.0%
checking the MD5 checksum for downloaded models...
dunnings-2018-fire-detection-pretrained-models.zip: OK
Unpacking the zip file...
Tidying up...
... completed -> required models are in models/
strong@foreverstrong:~/venv/tensorflow_work/fire-detection-cnn$

7. date / date -R

检查你的系统时钟，date / date -R。如果不正确，证书检查将失败。

strong@foreverstrong:~$ date
Sun Jul 21 16:53:57 CST 2019
strong@foreverstrong:~$ 
strong@foreverstrong:~$ date -R
Sun, 21 Jul 2019 16:55:09 +0800
strong@foreverstrong:~$