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visits member for 2 years, 11 months
seen Jul 20 '13 at 11:38

Jun
5
comment Bacula windows client could not connect to Bacula director
Can you do the following as debugging procedures: 1) Change the director address to the public address instead of the local address and restart Bacula 2) Run bconsole on your server hosting the Bacula director and execute status <client-name-here> and report the status of these two commands? And yes, wrap text and make sure your configuration file is legible in the preview - if it isn't, then we can't quite read it easily. I'd say that your question requires a bit more debugging effort from your end. Considering that it's been migrated from StackOverflow, you are excused.
Jun
4
comment Only one domain is not resolving via Windows DNS server at multiple locations, but is at others
Enable EDNS and get a packet capture using Wireshark for port 53 on the DNS server in question. Also if you provide the domain name you are facing issues with then I can dig around from here to have a look.
Jun
4
comment Cache updates when migrating DNS from one provider to another
In my opinion, your question warrants a new post/question. It's related the OP's question, but is a very specific case and deals with DNS security.
Jun
4
comment Cache updates when migrating DNS from one provider to another
"As an optional step, check the TTLs of arriving data looking for RRs with excessively long TTLs. If a RR has an excessively long TTL, say greater than 1 week, either discard the whole response, or limit all TTLs in the response to 1 week." In addition to the checks afforded offered by the distributed nature of DNS, you are also benefited by ICANN and IANA who regulate root, gTLD and enforce compliance in association with government appointed bodies like RIPE NCC, Nominet and AusRegistry for ccTLDs. A rogue operator, such as one you fear is going to be put out of business soon enough!
Jun
4
comment Cache updates when migrating DNS from one provider to another
RFC 1035 states that: "The resolver may encounter a situation where no addresses are available for any of the name servers named in SLIST, and where the servers in the list are precisely those which would normally be used to look up their own addresses. This situation typically occurs when the glue address RRs have a smaller TTL than the NS RRs marking delegation, or when the resolver caches the result of a NS search. The resolver should detect this condition and restart the search at the next ancestor zone, or alternatively at the root." (contd...)
Jun
4
comment Cache updates when migrating DNS from one provider to another
From what you are saying, com had an NS record for example.com pointing to oldserver.example.com with reasonable TTL values. It also had glue records pointing to IP of oldserver.example.com. You changed records at this level to point to newserver.example.com with the same reasonable TTL. However, oldserver.example.com is under rogue control and has very long TTL and you are worried that you may be unable to move away from oldserver.example.com as your DNS provider. (contd...)
Jun
4
comment Cache updates when migrating DNS from one provider to another
I think I do Sandman4, but that is not how caching DNS servers are supposed to work! There is a TTL applicable to each record in the chain. If the software for a caching/recursive nameserver is broken, or if it's configured to override TTLs to preserve bandwidth, there is not much you can do. But TTLs are to expire and queries should go out regularly to re-get records for each part of the chain. DNS isn't fool proof and is distributed. Which is why we have DNSSEC with client side recursive verification. DNSSEC is also vulnerable in the last mile should the recursive/caching be compromised.
Jun
4
comment Cache updates when migrating DNS from one provider to another
The scenario you specify above is only possible if records that form the chain to your zone's NS records never expire or change either. That is however not the case and queries go out to root nameservers on expiry of records that delegate out to TLDs and so on to nameservers of child zones as well. This is assuming that the software you are using isn't broken!
Jun
4
comment Cache updates when migrating DNS from one provider to another
@Sandman4, I don't think that resonates with the spirit of "This question asks about potential problem which may be experienced by everyone who is switching DNS hosting."
Jun
4
revised Cache updates when migrating DNS from one provider to another
Accommodated @Sandman4's comments.
Jun
4
comment Cache updates when migrating DNS from one provider to another
@Sandman4, you are right - in that case only the TTL will apply. The OP did not say what TLD is the parent, so I don't think we can assume the availability of rapid updates.
Jun
3
answered Cache updates when migrating DNS from one provider to another
Jun
3
answered Linux - Imaging backup solution?
Jun
1
comment multiple vlans routed on one nic? trunk?General? or Access?
Does each VLAN have a gateway, or are they completely isolated? If you want all VLANs to be routed out, does your gateway (ADSL modem/router) support VLAN tagging (802.1q)? When you say routed through the Endian appliance, do you mean that it behaves as a router or is it a passthrough/bridging/transparent firewall?
Jun
1
answered Windows Server 2008 R2 DNS Server Intermittently Unresponsive
May
31
comment How can I easily confirm in Linux that two separate directories have the exact same contents?
MikeB, by executing recursive long listing and passing that to md5sum, you'll be getting an md5sum of the directory listing, which'll exclude the content of files. If inode sizes on filesystems on either end were different then it could very well create a difference in file sizes too. Doing an md5sum on the content like originally suggested by @CamdenS. is better.
May
31
comment How do you apply development practices like version control, testing and continuous integration/deployment to system administration?
s/Marvin/Hudson/ - thanks for spotting that @thelsdj :-)
May
31
revised How do you apply development practices like version control, testing and continuous integration/deployment to system administration?
s/Marvin/Hudson/ - thanks for spotting that @thelsdj :-)
May
31
answered PostgreSQL automatic backup
May
31
comment Windows Server 2008 R2 DNS Server Intermittently Unresponsive
@Ablue, I'll wait for your packet capture. When you get it, please post a comment and use the @ symbol with my username so that I get a notification that you have the capture.