Re: bind and the limit of serial number ???
well ours is still working fine ! thats why I asked this question, we did not realize that it went over 32 bit boundary how can I understand if there is a problem or not? Evren On Sun, 23 Apr 2000, Dave Dunaway wrote: > > Put a number bigger than 2^32 and it will overflows. > > > is the bind have 32 bit unsigned integer variable for the serial > > number part of the dns records? > > if yes, it means that we cant have a number bigger than > > 4294967296 right? what happens if we have a bigger number? > > then bind takes it like modulus 2^32? or it is forbidden to > > have a bigger number? > > -- > > Dave. > > > Dave Dunaway > [EMAIL PROTECTED] > To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
Re: bind and the limit of serial number ???
On Sun, 23 Apr 2000, Evren Yurtesen wrote: > Hello, > > is the bind have 32 bit unsigned integer variable for the serial > number part of the dns records? > if yes, it means that we cant have a number bigger than > 4294967296 right? Somewhere I read something like: "The format MMDDnn" is often used for the serial number. We know this wil break in the year 4294, but we are not worried about that." > what happens if we have a bigger number? > then bind takes it like modulus 2^32? I once put in an extra digit in the serial number. This made a secondary use a serial number, which was larger than mine, and could probably be the modulus 2^32. I had to call the hostmaster there (A "3.rd secondary" hosted at our uplink) to get the zonefile removed, so the right one would be reloaded. > or it is forbidden to > have a bigger number? Not only forbidden, impossible... Leif To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
Re: bind and the limit of serial number ???
You can not be sure your secondary dns servers are picking up your zonefile, when you update the primary. On Sun, 23 Apr 2000, Evren Yurtesen wrote: > well ours is still working fine ! > thats why I asked this question, we did not realize that it went over 32 > bit boundary > how can I understand if there is a problem or not? > Evren > > On Sun, 23 Apr 2000, Dave Dunaway wrote: > > > > > Put a number bigger than 2^32 and it will overflows. > > > > > is the bind have 32 bit unsigned integer variable for the serial > > > number part of the dns records? > > > if yes, it means that we cant have a number bigger than > > > 4294967296 right? what happens if we have a bigger number? > > > then bind takes it like modulus 2^32? or it is forbidden to > > > have a bigger number? > > > > -- > > > > Dave. > > > > > > Dave Dunaway > > [EMAIL PROTECTED] > > > > > > To Unsubscribe: send mail to [EMAIL PROTECTED] > with "unsubscribe freebsd-hackers" in the body of the message > To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
Re: bind and the limit of serial number ???
:You can not be sure your secondary dns servers are picking up your :zonefile, when you update the primary. : You can 'reset' (roll-over) the serial number, but when you do so you have to realize that the secondaries may continue to cache the 'old' version of the zone file all the way up to the expiration time of the zone in the SOA (normally 3-days to a week). For manual updates of the zone file, I recommend using mmdd rather then mmddhhmm, and if you modify it twice in one day just increment the day (and hopefully real time will catch up to it again). For automatic updates (i.e. scripts that update zone files), I recommend simply starting the serial number at 1 and incrementing it on every update. Trying to make the serial number into a date for viewing ease is overrated. -Matt Matthew Dillon <[EMAIL PROTECTED]> To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
Re: bind and the limit of serial number ???
* Leif Neland ([EMAIL PROTECTED]) [000423 13:17]: > I once put in an extra digit in the serial number. > This made a secondary use a serial number, which was larger than mine, and > could probably be the modulus 2^32. > I had to call the hostmaster there (A "3.rd secondary" hosted at our > uplink) to get the zonefile removed, so the right one would be reloaded. Just FYI: if you make the serial number of a zone '0', secondary servers (bind at least) will *always* grab the zone from the master. It's intended to fix just the situation you had; set the serial to 0, leave it that way until all the slaves have picked up the new zone, then start using the proper numbering scheme again. It wastes bandwidth for a while if you have a large number of secondaries and/or a low refresh time, but it lets you fix a type without human intervention. -- j. James FitzGibbon [EMAIL PROTECTED] Targetnet.com Inc. Voice/Fax +1 416 306-0466/0452 To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
Re: bind and the limit of serial number ???
> > I once put in an extra digit in the serial number. > > This made a secondary use a serial number, which was larger than mine, and > > could probably be the modulus 2^32. > > I had to call the hostmaster there (A "3.rd secondary" hosted at our > > uplink) to get the zonefile removed, so the right one would be reloaded. > > Just FYI: if you make the serial number of a zone '0', secondary servers > (bind at least) will *always* grab the zone from the master. It's intended > to fix just the situation you had; set the serial to 0, leave it that way > until all the slaves have picked up the new zone, then start using the > proper numbering scheme again. It wastes bandwidth for a while if you have > a large number of secondaries and/or a low refresh time, but it lets you fix > a type without human intervention. This is a BIND feature, and should not be relied on. From RFC 1982: Caution should also be exercised before causing the serial number to be set to the value zero. While this value is not in any way special in serial number arithmetic, or to the DNS SOA serial number, many DNS implementations have incorrectly treated zero as a special case, with special properties, and unusual behaviour may be expected if zero is used as a DNS SOA serial number. There are better methods if you need to lower the serial number. The standard method, which is guaranteed to work, is to increase the serial number by 2^31-1 on the primary (largest increase allowed by serial number arithmetic, se RFC 1982), wait one refresh period (then the slave will have picked up the new serial number), and *then* set it to the desired value. Steinar Haug, Nethelp consulting, [EMAIL PROTECTED] To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
Re: bind and the limit of serial number ???
The generally accepted method (AFAIR) is mmddxx, where xx starts at 00 and is incremented for each change during that day. This allows for multiple updates in a single day without causing problems for situations such as 3 updates today followed by one update each day for the next 4 days ... Of course, if you never manually update the zone file, this isn't really an issue ;) On 23-Apr-00 Matthew Dillon wrote: > > For manual updates of the zone file, I recommend using mmdd rather > then mmddhhmm, and if you modify it twice in one day just increment > the day (and hopefully real time will catch up to it again). > > For automatic updates (i.e. scripts that update zone files), I recommend > simply starting the serial number at 1 and incrementing it on every > update. Trying to make the serial number into a date for viewing ease > is overrated. > Cheers, Colin To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
