Re: dns/ip resolve error in PASE

[Scott Klement <midrange-l@xxxxxxxxxxxxxxxx>]

Jay,

You're used to software that looks up host names using the getaddrinfo() 
(or older gethostbyname()) API that is provided by the OS.  These 
routines will look in the host table entries, and if not found, will do 
a DNS request to find the IP address that corresponds to a host name.

It seems that the software you're running in PASE (this has nothing to 
do with PASE or goLang, directly, you can write software like this in 
any language, environment -- I've written it in RPG, for example) is not 
using one of those functions, but is directly calling a DNS resolver.   
So it isn't looking at the host table, it's just trying to connect 
directly to a DNS server.

You can tell this because it says "53 ... read udp ... i/o timeout".     
UDP port 53 is the standard for a DNS server.  It is trying to send a 
request and get back a response, and isn't getting one.

As such, you need to point it to an active DNS server that knows how to 
resolve your names...  NOT add them to the host table.

It kind of blows my mind that someone working in a professional business 
environment would be putting host names into a host table instead of 
using DNS.   IBM i is capable of running BIND (the same DNS server used 
on most Unix systems) and IBM has documentation for it here:

https://www.ibm.com/docs/en/i/7.4?topic=services-domain-name-system

That is what he meant by "provide a service on port 53" -- he means run 
an actual DNS server instead of using the host table.


On 8/2/2021 2:27 PM, Jay Vaughn wrote:
> the actual error in PASE is...
> [SNIP]
> 2021-08-02T14:02:18.154Z        ERROR   SARAMA: Failed to connect to broker
> abc.xyz.com:9092: dial tcp: lookup abc.xyz.com on [::1]:53: read udp
> [::1]:56603->[::1]:53: i/o timeout
> [SNIP]
> We have ensured our tcp/ip host table entries are good and relevant to this
> process
> [SNIP]
> Our linux guy is suggesting to "provide a service on port 53"... but not
> quite sure what he is referring to.