Skip to main content

When you try to search from Safari address bar [Google] Safari freezes

I was using Apple Safari on Mac OS X Yosemite and later on El Capitan just fine when suddenly one day I couldn't search from Safari's address bar. My search engine provider was Google but even changing the provider in Safari's preferences did not resolve the problem. The text I entered stood there and nothing happened. It looked like Safari froze. Other browsers like Firefox and Chrome were working just fine, which was telling me it is not DNS at least network wise.

Then I found out Safari prefetches DNS. In terminal you just write:

defaults write com.apple.safari WebKitDNSPrefetchingEnabled -boolean false
This command disables DNS prefetching. If this solves your problem then this is where you need to troubleshoot. Something in connection with your router and DNS is not OK.


Photo of stalled Safari

Popular posts from this blog

Reason: [{LED=250 2.1.5 RESOLVER.GRP.Expanded; distribution list expanded};{MSG=};{FQDN=};{IP=};{LRT=}]

 If you got this error checking the mail flow for a distribution group, it means the distribution group is closed and only internal senders can send e-mail to this group. When outside user sends e-mail to this group you get  Reason: [{LED=250 2.1.5 RESOLVER.GRP.Expanded; distribution list expanded};{MSG=};{FQDN=};{IP=};{LRT=}] Set Delivery for this group to internal and external users and your problem will be solved. 

Netscaler vs Exchange 2019 "time out during ssl handshake stage

If you are using Citrix Netscaler as load balancer in front of Exchange 2019 server you must know this: Microsoft Exchange 2019 is secured by default and allows only TLS 1.2. Therefore default schannel settings are as follows (using IISCrypto tool from Nartac Software): While Citrix Netscaler offers following Cipher Suites: TLS_RSA_WITH_AES_256_CBC_SHA TLS_RSA_WITH_AES_128_CBC_SHA TLS_DHE_RSA_WITH_AES_256_CBC_SHA TLS_DHE_RSA_WITH_AES_128_CBC_SHA TLS_DHE_DSS_WITH_AES_256_CBC_SHA TLS_DHE_DSS_WITH_AES_128_CBC_SHA TLS_RSA_WITH_DES_CBC_SHA TLS_RSA_EXPORT_WITH_DES40_CBC_SHA TLS_RSA_EXPORT_WITH_RC2_CBC_40_MD5 TLS_DHE_DSS_WITH_DES_CBC_SHA TLS_DHE_DSS_EXPORT1024_WITH_DES_CBC_SHA TLS_DHE_DSS_EXPORT_WITH_DES40_CBC_SHA TLS_DHE_RSA_WITH_DES_CBC_SHA TLS_DHE_RSA_EXPORT_WITH_DES40_CBC_SHA TLS_RSA_EXPORT1024_WITH_RC2_CBC_56_MD5 TLS_DH_anon_WITH_DES_CBC_SHA TLS_DH_anon_WITH_AES_128_CBC_SHA TLS_DH_anon_WITH_AES_256_CBC_SHA TLS_DH_anon_EXPORT_WITH_DES40_CBC_SHA Now, you will fi

Ports that need to be open on Firewall for Edge Transport servers

Ports that need to be open on firewall for Edge Server subscription with Hub Server to function properly: For Inbound traffic: SMTP - TCP port 25 (from Internet) SMTP - TCP port 25 (from Edge server to Hub server on internal network) For Outbound traffic: SMTP - TCP/UDP port 25 (from Edge to Internet) SMTP - TCP/UDP port 25 (from Hub to Edge server) LDAP for EdgeSync - TCP port 50389 (from Hub to Edge server) Secure LDAP for EdgeSync - TCP port 50636 (from Hub to Edge server) Since Edge server needs to communicate with Hub server it is important that it can resolve Hub transport servers by FQDN and Hub transport servers must be able to resolve Edge servers by its FQDNs. To accomplish this you need to either open 53 (DNS) port and configure internal network adapter to use internal DNS but as a security precaution I would suggest to enter DNS records for Edge servers on local DNS manually and to fill hosts file on Edge servers with FQDNs for Hub transport servers.