[TriLUG] Griping about Time-Warner outage

[David Both]

Changing /etc/resolv.conf if you are using DHCP can be frustrating after a 
reboot because I used to forget that I had manually changed the file. Here are a 
couple options to help.

If you are using DHCP or static IPs on a system, and I assume it is Linux of 
some kind, you can add the DNS entries to 
/etc/sysconfig/network-scripts/ifcfg-eth0 (or appropriate NIC name).

DNS1=8.8.8.8
DNS2=8.8.4.4

Up to 3 are supported. My experience is that the DHCP provided name server is 
the 1st one in the list in /etc/resolv.conf, but this at least provides a 
failover after the brief, but annoying, timeout.

Another option is to set up /etc/resolv.conf and then be sure to set the 
immutable bit so that the NetworkManager service cannot change it.

chattr +i /etc/resolv.conf



On 08/01/2012 10:05 AM, Brian Henning wrote:
> Think I'll chime in on TWCBC support, with DNS in particular.
>
> TWCBC, at least in my segment, provides that good-old RFC-breaking domain
> search landing page instead of NXDOMAIN.  Example:
>
> $ host poop
> poop has address 66.152.109.110
> poop has address 69.16.143.110
> Host poop not found: 3(NXDOMAIN)
>
> A web browser of course will come up with "Armstrong Website Suggestions."
> Though that landing page provides an opt-out mechanism, it doesn't work.
> Setting everything to "Disabled" doesn't result in getting NXDOMAIN as the
> first response.
>
> I called tech support about it.  Their response?
>
> "Use someone else's DNS server."
>
> I guess I should've asked to talk to that person's manager, but it was late
> in the evening and I wasn't feeling like engaging in politics.
>
> My thanks to David Both for mentioning Google's public DNS servers.  I've
> just edited my resolv.conf file to point to them instead of TWC's.  Hooray!
>
> My $0.47 (adjusted for inflation),
> ~B
>
>
> -----Original Message-----
> From: trilug-bounces at trilug.org [mailto:trilug-bounces at trilug.org] On Behalf
> Of matt at noway2.thruhere.net
> Sent: Wednesday, August 01, 2012 9:50 AM
> To: Triangle Linux Users Group General Discussion
> Subject: Re: [TriLUG] Griping about Time-Warner outage
>
> It has been my experience too that TWC outages are caused primarily by a
> failure of DNS.  It is easy enough to verify with a numeric ping.
>
> Since switching to my own DNS (BIND) I haven't had this problem.  I have
> had to power reset the cable modem a few times since I switched to
> business class, whereas my residential Toshiba went a couple of years
> without a reset.
>
> With regards to their poor customer service, I have also found that the
> business class support is FAR better than the residential.  The
> residential internet support is heavily oriented around the PEBKAC model
> and fails when it is not.  For example, with my recent issue regarding
> their email relays getting put on RBL lists, when I contacted BC support,
> they asked me to show them a copy of the problem with a pastebin like
> site, which they then acknowledged that there was a problem, verified it
> with MXToolBox, and brought their security department in to the mix, and
> created an internal work order to have the culprit identified and shut
> down.  The residential help desk kept saying, "we don't see a problem with
> the account sir.  If your having problems with receiving spam you need to
> get a filter program."
>
>> Not everyone will want to go to the lengths that I have to deal with flaky
>> ISP DNS.
>>
>> I have had trouble with TWC DNS as well as DNS provided by a couple
>> previous
>> ISPs I have used. I use an internal caching name server with Google
>> (8.8.8.8 and
>> 8.8.4.4) as the forwarders. I have not experienced a DNS outage since
>> starting
>> that. I have tried OpenDNS as my forwarders, but they do too much
>> filtering of
>> "undesirable" IP addresses so I gave up on them. My "undesirable" is not
>> the
>> same as theirs. ;-)
>>
>> I have recently started using my DNS server for internal name resolution
>> instead
>> of /etc/hosts files, but that is intended as a learning experience for me.
>> And I
>> have learned a lot about DNS that way.
>>
>>
>
> -- 
>
>
> *********************************************************
> David P. Both, RHCE
> Millennium Technology Consulting LLC
> 919-389-8678
>
> dboth at millennium-technology.com
>
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>