Websites blocked in full transparent mode

Question

Hello, 
 I currently have a ASG320 and it is set up as full transparent proxy. When the transparent proxy is inline, we are not able to access certain sites (Cisco.com, youtube.com, 123rescute.com, slack.com, for example). Looking through the logs, we receive these messages: 
 
 2017:01:18-19:50:39 UTM9 httpproxy[26799]: id="0003" severity="info" sys="SecureWeb" sub="http" request="(nil)" function="plain_write_vector" file="epoll.c" line="1117" message="Write error on the epoll handler 84 (Broken pipe)"
2017:01:18-19:50:39 UTM9 httpproxy[26799]: id="0002" severity="info" sys="SecureWeb" sub="http" name="web request blocked" action="block" method="CONNECT" srcip="192.168.50.205" dstip="52.84.18.239" user="" group="" ad_domain="" statuscode="500" cached="0" profile="REF_DefaultHTTPProfile (Default Web Filter Profile)" filteraction="REF_DefaultHTTPCFFAction (Default content filter action)" size="517" request="0xdfda3200" url=" https://xxxxxx.slack.com/" referer="" error="Connection refused" authtime="0" dnstime="3" cattime="190" avscantime="0" fullreqtime="1020" device="0" auth="0" ua="" exceptions="" category="170" reputation="trusted" categoryname="Personal Network Storage"
2017:01:18-19:50:39 UTM9 httpproxy[26799]: id="0003" severity="info" sys="SecureWeb" sub="http" request="(nil)" function="plain_write_vector" file="epoll.c" line="1117" message="Write error on the epoll handler 83 (Broken pipe)"
2017:01:18-19:50:39 UTM9 httpproxy[26799]: id="0002" severity="info" sys="SecureWeb" sub="http" name="web request blocked" action="block" method="CONNECT" srcip="192.168.50.66" dstip="52.84.18.239" user="" group="" ad_domain="" statuscode="500" cached="0" profile="REF_DefaultHTTPProfile (Default Web Filter Profile)" filteraction="REF_DefaultHTTPCFFAction (Default content filter action)" size="517" request="0xa21f600" url=" https://xxxxxx.slack.com/" referer="" error="Connection refused" authtime="0" dnstime="3" cattime="117" avscantime="0" fullreqtime="1032" device="0" auth="0" ua="" exceptions="" category="170" reputation="trusted" categoryname="Personal Network Storage"
2017:01:18-19:50:39 UTM9 httpproxy[26799]: id="0003" severity="info" sys="SecureWeb" sub="http" request="(nil)" function="plain_write_vector" file="epoll.c" line="1117" message="Write error on the epoll handler 84 (Broken pipe)"
2017:01:18-19:50:39 UTM9 httpproxy[26799]: id="0002" severity="info" sys="SecureWeb" sub="http" name="web request blocked" action="block" method="CONNECT" srcip="192.168.50.205" dstip="52.84.18.239" user="" group="" ad_domain="" statuscode="500" cached="0" profile="REF_DefaultHTTPProfile (Default Web Filter Profile)" filteraction="REF_DefaultHTTPCFFAction (Default content filter action)" size="517" request="0xa21c000" url=" https://xxxxxx.slack.com/" referer="" error="Connection refused" authtime="0" dnstime="3" cattime="234" avscantime="0" fullreqtime="1106" device="0" auth="0" ua="" exceptions="" category="170" reputation="trusted" categoryname="Personal Network Storage"
2017:01:18-19:50:39 UTM9 httpproxy[26799]: id="0003" severity="info" sys="SecureWeb" sub="http" request="(nil)" function="plain_write_vector" file="epoll.c" line="1117" message="Write error on the epoll handler 83 (Broken pipe)"
2017:01:18-19:50:39 UTM9 httpproxy[26799]: id="0002" severity="info" sys="SecureWeb" sub="http" name="web request blocked" action="block" method="CONNECT" srcip="192.168.50.205" dstip="52.84.18.239" user="" group="" ad_domain="" statuscode="500" cached="0" profile="REF_DefaultHTTPProfile (Default Web Filter Profile)" filteraction="REF_DefaultHTTPCFFAction (Default content filter action)" size="517" request="0xa21d800" url=" https://xxxxxx.slack.com/" referer="" error="Connection refused" authtime="0" dnstime="3" cattime="170" avscantime="0" fullreqtime="1241" device="0" auth="0" ua="" exceptions="" category="170" reputation="trusted" categoryname="Personal Network Storage"
2017:01:18-19:50:39 UTM9 httpproxy[26799]: id="0003" severity="info" sys="SecureWeb" sub="http" request="(nil)" function="plain_write_vector" file="epoll.c" line="1117" message="Write error on the epoll handler 83 (Broken pipe)"
2017:01:18-19:50:39 UTM9 httpproxy[26799]: id="0002" severity="info" sys="SecureWeb" sub="http" name="web request blocked" action="block" method="CONNECT" srcip="192.168.50.66" dstip="52.84.18.239" user="" group="" ad_domain="" statuscode="500" cached="0" profile="REF_DefaultHTTPProfile (Default Web Filter Profile)" filteraction="REF_DefaultHTTPCFFAction (Default content filter action)" size="517" request="0xa343200" url=" https://xxxxxx.slack.com/" referer="" error="Connection refused" authtime="0" dnstime="4" cattime="152" avscantime="0" fullreqtime="1169" device="0" auth="0" ua="" exceptions="" category="170" reputation="trusted" categoryname="Personal Network Storage" 
 2017:01:18-20:14:33 UTM9 httpproxy[26799]: id="0002" severity="info" sys="SecureWeb" sub="http" name="web request blocked" action="block" method="GET" srcip="192.168.50.125" dstip="23.58.115.155" user="" group="" ad_domain="" statuscode="502" cached="0" profile="REF_DefaultHTTPProfile (Default Web Filter Profile)" filteraction="REF_DefaultHTTPCFFAction (Default content filter action)" size="2500" request="0xdedde400" url=" http://www.cisco.com/" referer="" error="Connection refused" authtime="0" dnstime="386" cattime="28305" avscantime="0" fullreqtime="31161" device="0" auth="0" ua="Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.87 Safari/537.36" exceptions="" category="105" reputation="trusted" categoryname="Business"
2017:01:18-20:14:33 UTM9 httpproxy[26799]: id="0003" severity="info" sys="SecureWeb" sub="http" request="(nil)" function="plain_write_vector" file="epoll.c" line="1117" message="Write error on the epoll handler 85 (Connection refused)"
2017:01:18-20:14:33 UTM9 httpproxy[26799]: id="0003" severity="info" sys="SecureWeb" sub="http" request="(nil)" function="plain_write_vector" file="epoll.c" line="1117" message="Write error on the epoll handler 85 (Connection refused)"
2017:01:18-20:14:33 UTM9 httpproxy[26799]: id="0003" severity="info" sys="SecureWeb" sub="http" request="0xdfc33000" function="send_request_headers" file="request.c" line="907" message="write() on AF 2 socket to 23.58.115.155 failed: Connection refused"
2017:01:18-20:14:33 UTM9 httpproxy[26799]: id="0002" severity="info" sys="SecureWeb" sub="http" name="web request blocked" action="block" method="GET" srcip="192.168.50.125" dstip="23.58.115.155" user="" group="" ad_domain="" statuscode="502" cached="0" profile="REF_DefaultHTTPProfile (Default Web Filter Profile)" filteraction="REF_DefaultHTTPCFFAction (Default content filter action)" size="2511" request="0xdfc33000" url=" www.cisco.com/favicon.ico" referer=" http://www.cisco.com/" error="Connection refused" authtime="0" dnstime="131" cattime="24687" avscantime="0" fullreqtime="25891" device="0" auth="0" ua="Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/55.0.2883.87 Safari/537.36" exceptions="" category="105" reputation="trusted" categoryname="Business" I've tried adding in those websites in the exceptions list, and still am unable to access. I've worked with a couple of engineers, and still am unable to resolve. I've been looking through the different forums, and I have yet to find a solution regarding blocked websites in transparent mode. Was just wondering if anybody has a solution to this. Thank you in advance

BAlfson · Answer

With a statuscode in the 500s, Mark, if an Exception for Antivirus (plus 'SSL scanning' and 'Certificate trust check' for HTTPS) doesn't solve the problem, you will need to skip the Proxy for the site. 
 Cheers - Bob

BAlfson · Answer

In the DNS Group for slack, change the Hostname field to ca.slack-edge.com . In the one for Cisco, change it to www.cisco.com . Any better luck now? 
 Cheers - Bob