Re: [avahi] Is it possible to customize #define AVAHI_DEFAULT_TTL_HOST_NAME and #define AVAHI_DEFAULT_TTL, rather than embedding them statically in the code?
On Tue, Jul 10, 2012 at 4:55 AM, Patrick Oppenlander pattyo.li...@gmail.com mailto:pattyo.li...@gmail.com wrote: On 05/07/12 20:19, Ajay Garg wrote: Hi all. I ran into a issue, as described at https://bugs.freedesktop.org/show_bug.cgi?id=51501 This behaviour is not a bug. It's a side-effect of how MDNS is (intentionally) designed. Your bug report states that the callback is not called. It will in fact be called, it just takes a long time. Yes, I think it would. But the callback is not called after 120 seconds. May be after 75 minutes.. but I haven't waited that long enough :) Also, as per https://tools.ietf.org/html/draft-cheshire-dnsext-multicastdns-15#section-10, the standard says that the timeout is expected to be 120 seconds. I think you're misunderstanding how the TTLs are used. the 120 seconds refers to host specific records -- i.e. records that are available after a resolve. A client application is not notified when these records expire as they are transient. The 75 minute TTL is for everything else, including PTR records, which is what you are interested in. I've never used Telepathy so I can't really offer suggestions on how to proceed with your issue, but keep in mind that DNS-SD was never designed to provide an iron-clad guarantee that a service is available. The only way to determine that a service is genuinely available is to first resolve it, and if the resolve succeeds attempt to connect. Patrick ___ avahi mailing list avahi@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/avahi
Re: [avahi] Is it possible to customize #define AVAHI_DEFAULT_TTL_HOST_NAME and #define AVAHI_DEFAULT_TTL, rather than embedding them statically in the code?
Thanks Patrick for the reply. On Tue, Jul 10, 2012 at 11:38 AM, Patrick Oppenlander pattyo.li...@gmail.com wrote: On Tue, Jul 10, 2012 at 4:55 AM, Patrick Oppenlander pattyo.li...@gmail.com wrote: On 05/07/12 20:19, Ajay Garg wrote: Hi all. I ran into a issue, as described at https://bugs.freedesktop.org/show_bug.cgi?id=51501 This behaviour is not a bug. It's a side-effect of how MDNS is (intentionally) designed. Your bug report states that the callback is not called. It will in fact be called, it just takes a long time. Yes, I think it would. But the callback is not called after 120 seconds. May be after 75 minutes.. but I haven't waited that long enough :) Also, as per https://tools.ietf.org/html/draft-cheshire-dnsext-multicastdns-15#section-10, the standard says that the timeout is expected to be 120 seconds. I think you're misunderstanding how the TTLs are used. the 120 seconds refers to host specific records -- i.e. records that are available after a resolve. A client application is not notified when these records expire as they are transient. The 75 minute TTL is for everything else, including PTR records, which is what you are interested in. I've never used Telepathy so I can't really offer suggestions on how to proceed with your issue, but keep in mind that DNS-SD was never designed to provide an iron-clad guarantee that a service is available. The only way to determine that a service is genuinely available is to first resolve it, and if the resolve succeeds attempt to connect. Yes, that's right. But the use-case we need to handle (getting to know when a client has disconnected from the telepathy-salut network) wouldn't be solved by this. Therein, we need to have a mechanism by which the dis-connectivity may be known. Unfortunately, polling (or pseudo-polling) is the only ultimate way (since the going-disconnected-buddy doesn't give the goodbye signal, since no network-medium is available). So, perhaps a client notification *should* get notified, once the transient-resolved-records expire??!! Just my 2 cents :) Thanks and Regards, Ajay Patrick ___ avahi mailing list avahi@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/avahi ___ avahi mailing list avahi@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/avahi
Re: [avahi] Is it possible to customize #define AVAHI_DEFAULT_TTL_HOST_NAME and #define AVAHI_DEFAULT_TTL, rather than embedding them statically in the code?
On 11/07/12 01:17, Ajay Garg wrote: So, perhaps a client notification *should* get notified, once the transient-resolved-records expire??!! This doesn't help as these records always expire after two minutes. They are not refreshed unless another resolve is requested. Patrick ___ avahi mailing list avahi@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/avahi
Re: [avahi] Is it possible to customize #define AVAHI_DEFAULT_TTL_HOST_NAME and #define AVAHI_DEFAULT_TTL, rather than embedding them statically in the code?
Hi all. I have written a patch, that solves the issue https://bugs.freedesktop.org/show_bug.cgi?id=51501#c5 The patch is available at http://people.sugarlabs.org/ajay/root/freedesktop_bug_51501/common-patch-for-f14-and-f17/customize-avahi-default-ttl-values.patch Will be glad to have it considered, and have feedback/criticism/whatever. Thanks and Regards, Ajay On Thu, Jul 5, 2012 at 7:32 PM, Ajay Garg ajaygargn...@gmail.com wrote: Hi all. Just found about /etc/avahi/avahi-daemon.conf. That would do it !!! (of course after patching avahi to read-in the two new values). Will be back soon with a patch :) Regards, Ajay On Thu, Jul 5, 2012 at 3:49 PM, Ajay Garg ajaygargn...@gmail.com wrote: Hi all. I ran into a issue, as described at https://bugs.freedesktop.org/show_bug.cgi?id=51501 I followed these steps :: a) I changed the values to #define AVAHI_DEFAULT_TTL_HOST_NAME (20) #define AVAHI_DEFAULT_TTL (20) b) Re-compiled the RPMS c) Upgraded to these new RPMS on my F17. And voila, the contacts-disappearance signals did emit (after about 20 seconds) !!! The same approach solved the issue on F14 as well !!! So, now I intend to make the values of these 2 #defines customizable. My queries are :: (i) Is it possible already? (ii) If answer to (i) is no, perhaps GConf might help? The thing that worries me is in what context should Gconf-entries be populated, since avahi runs as a daemon. Will be grateful to a reply. Thanks and Regards, Ajay ___ avahi mailing list avahi@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/avahi
Re: [avahi] Is it possible to customize #define AVAHI_DEFAULT_TTL_HOST_NAME and #define AVAHI_DEFAULT_TTL, rather than embedding them statically in the code?
On 05/07/12 20:19, Ajay Garg wrote: Hi all. I ran into a issue, as described at https://bugs.freedesktop.org/show_bug.cgi?id=51501 This behaviour is not a bug. It's a side-effect of how MDNS is (intentionally) designed. Your bug report states that the callback is not called. It will in fact be called, it just takes a long time. I followed these steps :: a) I changed the values to #define AVAHI_DEFAULT_TTL_HOST_NAME (20) #define AVAHI_DEFAULT_TTL (20) This is a pretty bad idea as these records will need to be refreshed at 17 second intervals. Some people already consider mDNS to be a chatty protocol [1]. This kind of thing just exacerbates the problem. Patrick [1] http://www.net.princeton.edu/filters/mdns.html ___ avahi mailing list avahi@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/avahi
Re: [avahi] Is it possible to customize #define AVAHI_DEFAULT_TTL_HOST_NAME and #define AVAHI_DEFAULT_TTL, rather than embedding them statically in the code?
On Tue, Jul 10, 2012 at 4:55 AM, Patrick Oppenlander pattyo.li...@gmail.com wrote: On 05/07/12 20:19, Ajay Garg wrote: Hi all. I ran into a issue, as described at https://bugs.freedesktop.org/show_bug.cgi?id=51501 This behaviour is not a bug. It's a side-effect of how MDNS is (intentionally) designed. Your bug report states that the callback is not called. It will in fact be called, it just takes a long time. Yes, I think it would. But the callback is not called after 120 seconds. May be after 75 minutes.. but I haven't waited that long enough :) Also, as per https://tools.ietf.org/html/draft-cheshire-dnsext-multicastdns-15#section-10, the standard says that the timeout is expected to be 120 seconds. So, at least making #define AVAHI_DEFAULT_TTL_HOST_NAME #define AVAHI_DEFAULT_TTL configurable (and not hard-coded), would make it more convenient for personal customizations. Just my 2 cents :) Thanks and Regards, Ajay I followed these steps :: a) I changed the values to #define AVAHI_DEFAULT_TTL_HOST_NAME (20) #define AVAHI_DEFAULT_TTL (20) This is a pretty bad idea as these records will need to be refreshed at 17 second intervals. Some people already consider mDNS to be a chatty protocol [1]. This kind of thing just exacerbates the problem. Patrick [1] http://www.net.princeton.edu/filters/mdns.html ___ avahi mailing list avahi@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/avahi ___ avahi mailing list avahi@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/avahi
Re: [avahi] Is it possible to customize #define AVAHI_DEFAULT_TTL_HOST_NAME and #define AVAHI_DEFAULT_TTL, rather than embedding them statically in the code?
Hi all. Just found about /etc/avahi/avahi-daemon.conf. That would do it !!! (of course after patching avahi to read-in the two new values). Will be back soon with a patch :) Regards, Ajay On Thu, Jul 5, 2012 at 3:49 PM, Ajay Garg ajaygargn...@gmail.com wrote: Hi all. I ran into a issue, as described at https://bugs.freedesktop.org/show_bug.cgi?id=51501 I followed these steps :: a) I changed the values to #define AVAHI_DEFAULT_TTL_HOST_NAME (20) #define AVAHI_DEFAULT_TTL (20) b) Re-compiled the RPMS c) Upgraded to these new RPMS on my F17. And voila, the contacts-disappearance signals did emit (after about 20 seconds) !!! The same approach solved the issue on F14 as well !!! So, now I intend to make the values of these 2 #defines customizable. My queries are :: (i) Is it possible already? (ii) If answer to (i) is no, perhaps GConf might help? The thing that worries me is in what context should Gconf-entries be populated, since avahi runs as a daemon. Will be grateful to a reply. Thanks and Regards, Ajay ___ avahi mailing list avahi@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/avahi
