Pulp

As shown below, if a network error occurs during a sync and several requests fail, the sync will skip the rest of its downloads. This is good, because trying to make thousands more requests to a struggling or missing remote service could take a lot of time, could make that remove service's problems worse, and is unlikely to succeed.

It would be helpful to document that behavior. I think this logic is in nectar, so most importers will behave this way. Here is an example of that behavior "in the wild":

[root@ibm-x3550m3-06 ~]# rpm -qa pulp-server
pulp-server-2.7.0-0.7.beta.el7.noarch
[root@ibm-x3550m3-06 ~]# 

[root@ibm-x3550m3-06 ~]# pulp-admin node  sync run --node-id node1
This command may be exited via ctrl+c without affecting the request.

[-]
Accepted...

(1/1) Repository: centos
[====                                              ] 9%

Error occurred during synchronization, check the child node logs for details

+----------------------------------------------------------------------+
                       Child Node Synchronization
+----------------------------------------------------------------------+

Repository: 
  Action:          Merged
  Content Sources: 
    Downloads:     
      Source Id:       Parent Node
      Total Failed:    4611
      Total Succeeded: 490
    Total Sources: 0
  Id:              centos
  Units:           
    Added:   490
    Removed: 0
    Updated: 0

+----------------------------------------------------------------------+
               The following [4611] errors were reported
+----------------------------------------------------------------------+

- 01: Received error [A connection error occurred] while downloading a unit file
at URL
[https://ibm-x3550m3-06.lab.eng.brq.redhat.com/pulp/nodes/https/repos/centos/con
tent/rpm/evolution-mapi-devel/3.8.5/6.el7/i686/ec7af664520b926516f473cf086388373
14ad9d5bc2a03af79d945228d49f7ca/evolution-mapi-devel-3.8.5-6.el7.i686.rpm] for
repository [centos]. The cause could be that the repository has not been
published.

- 02: Received error [Download skipped] while downloading a unit file at URL
[https://ibm-x3550m3-06.lab.eng.brq.redhat.com/pulp/nodes/https/repos/centos/con
tent/rpm/OpenEXR/1.7.1/7.el7/x86_64/4abca5307be39571089dd481eeb307bcf29fbb473629
005cae5721079108546a/OpenEXR-1.7.1-7.el7.x86_64.rpm] for repository [centos].
The cause could be that the repository has not been published.

- 03: Received error [Download skipped] while downloading a unit file at URL
[https://ibm-x3550m3-06.lab.eng.brq.redhat.com/pulp/nodes/https/repos/centos/con
tent/rpm/texlive-charter-doc/svn15878.0/32.el7/noarch/e068aee3536f1e724610ebe09b
d9c077fa82275d147df9a45e55abead8e18ddd/texlive-charter-doc-svn15878.0-32.el7.noa
rch.rpm] for repository [centos]. The cause could be that the repository has not
been published.

- 04: Received error [Download skipped] while downloading a unit file at URL
[https://ibm-x3550m3-06.lab.eng.brq.redhat.com/pulp/nodes/https/repos/centos/con
tent/rpm/mythes-uk/1.6.5/6.el7/noarch/753a0d54ce20196ac1cc61914258f38f8f3cd13f9d
a280fc562f59c9b503062a/mythes-uk-1.6.5-6.el7.noarch.rpm] for repository
[centos]. The cause could be that the repository has not been published.

- 05: Received error [Download skipped] while downloading a unit file at URL
[https://ibm-x3550m3-06.lab.eng.brq.redhat.com/pulp/nodes/https/repos/centos/con
tent/rpm/libbluray-devel/0.2.3/5.el7/x86_64/424fbab8446ab76bab7454ddac4b98daa6aa
b71f461ec672cdaf0de84c8c99a5/libbluray-devel-0.2.3-5.el7.x86_64.rpm] for
repository [centos]. The cause could be that the repository has not been
published.

- 06: Received error [Download skipped] while downloading a unit file at URL
[https://ibm-x3550m3-06.lab.eng.brq.redhat.com/pulp/nodes/https/repos/centos/con
tent/rpm/libgnome/2.32.1/9.el7/i686/59c0d5006cc901129acecaee16f7cfdda57873d8c520
ace99c63ac6036124203/libgnome-2.32.1-9.el7.i686.rpm] for repository [centos].
The cause could be that the repository has not been published.

- 07: Received error [Download skipped] while downloading a unit file at URL
[https://ibm-x3550m3-06.lab.eng.brq.redhat.com/pulp/nodes/https/repos/centos/con
tent/rpm/alsa-plugins-vdownmix/1.0.27/3.el7/i686/ffd0f28a6540ec51b9abc6843caa1f3
a461554097b5bf49044f0f55bb8fe18ca/alsa-plugins-vdownmix-1.0.27-3.el7.i686.rpm]
for repository [centos]. The cause could be that the repository has not been
published.