According to documentation, older versions of KMS are available for download at http://ubuntu.kurento.org/pool/main/k/.
There seems to be only one version available here (6.0.0), and even after installing all of the dependencies, the server fails to run due to dependency complications. It appears there isn't a trusty version of the gstreamer1.5-kmsnice dependency (http://ubuntu.kurento.org/pool/main/libk/libkmsnice/) which is perhaps related.
In any case, I would prefer to downgrade to version 6.1.1, which is the last known working installation on my AWS setup, but no versions below 6.3.2 (besides 6.0.0) appear available any longer.
My question is: Is there any supported, official way to downgrade versions?
ubuntu@ec2:~$ apt-cache showpkg kurento-media-server-6.0
Package: kurento-media-server-6.0
Versions:
6.3.3~20160130183418.2.g038c3f9.trusty (/var/lib/apt/lists/ubuntu.kurento.org_dists_trusty-dev_kms6_binary-amd64_Packages) (/var/lib/dpkg/status)
Description Language:
File: /var/lib/apt/lists/ubuntu.kurento.org_dists_trusty-dev_kms6_binary-amd64_Packages
MD5: 4ffd6c93aad3db63d24cb40393e99fc0
6.3.2.trusty (/var/lib/apt/lists/ubuntu.kurento.org_dists_trusty_kms6_binary-amd64_Packages)
Description Language:
File: /var/lib/apt/lists/ubuntu.kurento.org_dists_trusty-dev_kms6_binary-amd64_Packages
MD5: 4ffd6c93aad3db63d24cb40393e99fc0
Reverse Depends:
kurento-server,kurento-media-server-6.0 6.3.2.trusty
kurento-media-server-6.0-dev,kurento-media-server-6.0 6.3.2.trusty
kurento-media-server-6.0-dbg,kurento-media-server-6.0 6.3.2.trusty
kurento-server,kurento-media-server-6.0 6.3.3~20160130183418.2.g038c3f9.trusty
kurento-media-server-6.0-dev,kurento-media-server-6.0 6.3.3~20160130183418.2.g038c3f9.trusty
kurento-media-server-6.0-dbg,kurento-media-server-6.0 6.3.3~20160130183418.2.g038c3f9.trusty
Dependencies:
6.3.3~20160130183418.2.g038c3f9.trusty - kms-core-6.0 (2 6.3.1) kms-jsonrpc-1.0 (0 (null)) kmsjsoncpp (0 (null)) libboost-filesystem1.55.0 (0 (null)) libboost-log1.55.0 (0 (null)) libboost-program-options1.55.0 (0 (null)) libboost-system1.55.0 (0 (null)) libboost-thread1.55.0 (0 (null)) libc6 (2 2.14) libgcc1 (2 1:4.1.1) libglib2.0-0 (2 2.41.1) libglibmm-2.4-1c2a (2 2.36.2) libgstreamer1.5-0 (2 1.7.1.1~20160129140239.197.g1873db8.trusty) libsigc++-2.0-0c2a (2 2.0.2) libssl1.0.0 (2 1.0.0) libstdc++6 (2 4.8.1) binutils (0 (null)) gstreamer1.5-plugins-base (2 1.7.0~0) gstreamer1.5-libav (2 1.7.0~0) gstreamer1.5-plugins-bad (2 1.7.0~0) gstreamer1.5-plugins-good (2 1.7.0~0) gstreamer1.5-plugins-ugly (2 1.7.0~0) kms-elements-6.0 (2 6.3.1) kms-filters-6.0 (2 6.3.0) kurento (0 (null)) kurento (0 (null)) kurento-media-server (0 (null)) kurento (0 (null)) kurento-media-server (0 (null))
6.3.2.trusty - kms-core-6.0 (2 6.3.1) kms-jsonrpc-1.0 (0 (null)) kmsjsoncpp (0 (null)) libboost-filesystem1.55.0 (0 (null)) libboost-log1.55.0 (0 (null)) libboost-program-options1.55.0 (0 (null)) libboost-system1.55.0 (0 (null)) libboost-thread1.55.0 (0 (null)) libc6 (2 2.14) libgcc1 (2 1:4.1.1) libglib2.0-0 (2 2.41.1) libglibmm-2.4-1c2a (2 2.36.2) libgstreamer1.5-0 (2 1.7.1.1~20160128135743.197.g1873db8.trusty) libsigc++-2.0-0c2a (2 2.0.2) libssl1.0.0 (2 1.0.0) libstdc++6 (2 4.8.1) binutils (0 (null)) gstreamer1.5-plugins-base (2 1.7.0~0) gstreamer1.5-libav (2 1.7.0~0) gstreamer1.5-plugins-bad (2 1.7.0~0) gstreamer1.5-plugins-good (2 1.7.0~0) gstreamer1.5-plugins-ugly (2 1.7.0~0) kms-elements-6.0 (2 6.3.1) kms-filters-6.0 (2 6.3.0) kurento (0 (null)) kurento (0 (null)) kurento-media-server (0 (null)) kurento (0 (null)) kurento-media-server (0 (null))
Provides:
6.3.3~20160130183418.2.g038c3f9.trusty -
6.3.2.trusty -
Reverse Provides:
I am running an Ubuntu 14.04.3 LTS (trusty) instance using Amazon's EC2.
According to Kurento's bug tracker, downgrading has been a requested feature, and while they would like to address this, it is not a priority.
https://github.com/Kurento/bugtracker/issues/31
While this is unfortunate, my immediate problem was fixed by purging the dependencies and doing a complete re-install (dependencies and all). It turned out there was a configuration file format and general dependency library mismatch.
apt-get remove --purge kurento-media-server-6.0
apt-get install kurento-media-server-6.0
https://github.com/Kurento/bugtracker/issues/24#issuecomment-178790595