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New Member

Regex issue post X8 Upgrade

I see the Regular Expression that handles the Calls to Internet Via DNS Zone, which was working properly till my X7 versions has stopped from X8.


The above regex will only allow non local domains to be queried to the DNS.

But, we see that the regex is now failing to process non local domain addresses. Is there any changes to regex behavior in X8...?


VIP Purple

Regex issue post X8 Upgrade

Wanted to add to Rameez's post, we use (?!.*@%localdomains%$).*, and it fails as well.  Prior to X8.1 it worked fine.

VIP Purple

Re: Regex issue post X8 Upgrade

Although this did work..


The Negative lookahead and lookbehind noted in the online help for regular expressions that provide examples on how to do this don't seem to work without a little tweaking.

(?!.*$).* matches any string that does not end with

Re: Regex issue post X8 Upgrade

I would love to here a response from Cisco on this one as well....

And cheers to Patrick for the RegEx edit

Many thanks


VIP Purple

Has anyone from Cisco been

Has anyone from Cisco been able to figure this one out , since the upgrade of VCS x8.1 breaks the negative lookahead and lookbehind? Either the two regex strings need to be recognized properly by the VCS, or the help documents need to be updated to include the extra characters added to the regex string to make them work with the current version of the VCS.

Patrick,i tried locate tool


i tried locate tool in my lab for the regex "(?!.*@%localdomains%.*$).*" and it works properly. can you please give more details ?



VIP Purple

Alok -Both negative lookahead

Alok -

Both negative lookahead and lookbehind fail for me when I do a check pattern.  I've copied the example out of the online help and replaced inserted %localdomains%.  Even you're noted example failed for me.

VIP Purple

Noticed someone opened a TAC

Noticed someone opened a TAC case for the negative lookbehind regex issue in the X8.x software.


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