Subject: Re: x2gobroker-ssh big delay in session status recovery

From: Mike Gabriel <[email-masked]>
Date: Thu, 13 Sep 2018 12:27:15 +0000

Dear Miguel,

> Package: x2gobroker
> Version: 0.0.3.1
>
> When x2gobroker-ssh is used with system with not IPv6 configured,  
> this generate very big delays in x2gobroker listsession task.
>
> Before some research, the problem become from x2gobroker.utils  
> portscan function.
>
> This function propagates a delay in all agents call because it tests  
> first the IPV6 connection:
>
> /ip_proto = 0////try:////socket.getaddrinfo(addr, None,  
> socket.AF_INET6)////ip_proto = 6////except  
> socket.gaierror:////try:////socket.getaddrinfo(addr, None,  
> socket.AF_INET)////ip_proto = 4////except socket.gaierror:////# we  
> can't find a valid address for this host, so returning a  
> failure...////return False /This will be fixed testing IPv4 first or  
> more easily, setting a new option in config to select the ip protocol.
>

A while ago you reported the above issue.

I tested this now.

The portscan function in x2gobroker.utils is really fast when  
detecting that a remote host is not IPv6 supportive. It basically is a  
fast DNS query.

Is it so, that your client system has IPv4 disabled entirely (in the  
kernel)? Or what exactly did you mean by "When x2gobroker-ssh is used  
with system with not IPv6 configured..."?

I am willing to do more test, please provide more info. You possibly  
also have found a fix meanwhile. If so, I'd be happy, if you could  
share it.

Thanks
Mike

-- 

DAS-NETZWERKTEAM
mike gabriel, herweg 7, 24357 fleckeby
mobile: +49 (1520) 1976 148
landline: +49 (4354) 8390 139

GnuPG Fingerprint: 9BFB AEE8 6C0A A5FF BF22  0782 9AF4 6B30 2577 1B31
mail: [email-masked], http://das-netzwerkteam.de