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Dave1013_121746's avatar
Dave1013_121746
Icon for Nimbostratus rankNimbostratus
Oct 30, 2014

Certificate alternate subject names truncated at 255 characters

I need to be able to verify whether a certificate covers a specific subject. But I run into scenarios where the alternate subjects are long and the iControl API truncates them at 255 characters. Th...
application delivery
devops
iControl
LTM
management
Arnaud_Lemaire's avatar
Arnaud_Lemaire
Icon for Employee rankEmployee
Oct 31, 2014

The maximum length of a DNS name is 255 octets. This is spelled out in RFC 1035 section 2.3.4

 

2.3.4. Size limits Various objects and parameters in the DNS have size limits. They are listed below. Some could be easily changed, others are more fundamental.

 

labels 63 octets or less

 

names 255 octets or less

 

TTL positive values of a signed 32 bit number.

 

UDP messages 512 octets or less