1. FAQ Overview
This informal FAQ is designed to assist helpdesks and IT Support Staff across the University in resolving issues with the Nexus service. It also contains additional detail on supported protocols to inform and assist ITSS.
For historical information concerning the migration to Nexus, please see Historical notes relating to migration from Herald to Nexus.
2. Email Service
The following methods of access are supported:
|Nexus POP||110/995||pop.nexus.ox.ac.uk / 22.214.171.124||POP3 connections|
|Nexus IMAP||143/993||imap.nexus.ox.ac.uk / 126.96.36.199||Secured IMAP|
|HTTPS||443||nexus.ox.ac.uk / 188.8.131.52||Secured HTTP connections for OWA, OutlookAnywhere, EWS, OAB, and Availabilty Service|
|HTTPS||443||autodiscover.nexus.ox.ac.uk / 184.108.40.206||Secured HTTP connections for Autodiscover Service|
|HTTP||80||autodiscoverredirect.nexus.ox.ac.uk / 220.127.116.11||HTTP redirect for Autodiscover Service|
The URL to use for clients that utilise EWS is https://nexus.ox.ac.uk/ews/exchange.asmx.
3. Unsupported Protocols
The following methods of access are not supported:
|MAPI||Various||Unencrypted direct MAPI connections - Use OutlookAnywhere instead (RPC/HTTPS)|
4. Resource Mailboxes
5. Distribution Lists
6. Global Address List (GAL)
For each account you needed to supply:
Accounts can be unhidden on request.
7. Project Accounts
Note: A "user" of a project account is not authorised to request SendAs or SendOnBehalf rights unless they own the project account.
8. Junk Email/spam Filtering
[Automatically filter junk e-mail]" setting in the
Junk E-mail screen is enabled.
The Junk mail filters on Nexus are not set to automatically discard email that passes a certain spam scoring threshold. To compensate for this, the Nexus Junk E-mail folder automatically deletes emails from the Junk E-mail folder (and ‘Deleted Items’) after 90 days. Some users are annoyed that some persistent spam, or irksome personal messages still arrive in their Junk E-mail folder. These people can be helped by either creating a rule on the Junk E-mail folder to delete certain emails immediately, or in the judicious use of Blocked Senders. See: http://www.oucs.ox.ac.uk/nexus/web/light_guide.xml?ID=filtering
The spam-filtering process is explained in detail here: http://www.oucs.ox.ac.uk/nexus/itss/message-flow.xml
9. What happens to a user's mailbox when their University Card expires?
When someone's University Card expires and they leave Oxford (and this notably includes "student leavers") their mailbox is usually deleted after 3 months. Departing users can usually extend this period if they ask for an extension at the IT Services Help Centre.
Users can set up forwarding that works for 2 months following departure/card expiry.
N.B. OOF = Out of facility message = Out of Office = Vacation Autoreply
Consider 3 categories of departing users: (A) Users who have forwarding set; (B) users who have a vacation message set (OOF); (C) users who have neither OOF nor forwarding set.
On card expiry, all 3 groups of users cease to have access to their mailboxes. For users in groups A and B, nothing else happens until the end of month 2. Users in group C have an OOF created saying that, "This account is scheduled for deletion. It is unlikely that your message will be read." (Also, if a mailbox belonging to group B has its OOF expire or switch off before the end of two months, that change should be detected within hours and the standard message applied.) At the end of month 2, mailboxes are 'detached' (or 'disabled'), and the routing tables are changed so that mail will not enter Nexus from outside. After a further one month, the mailboxes are deleted, but remain on tape for about 60 further days. (Tape retention policy is subject to change, however, and should be detailed in the Exchange SLD).
See also http://www.oucs.ox.ac.uk/registration/finish/index.xml?ID=email
10. Does using a NAT (or NAPT) device cause problems with Nexus?
In short, yes it can. There is a default limit to the number of connections per minute that are accepted from a single IP address. This can be caused by the sheer numbers of users behind a Network Address (and Port) Translation device and/or by some users having a large number of connections being opened rapidly. Users may find the interface via Outlook or Outlook Web App to be very slow or intermittently problematic. They may also see "This webpage is not available" when trying to log in to OWA or SharePoint.
Note that the limit applies to usage of both Exchange and SharePoint. It is often the multiple connections that can often occur per user when interacting with Exchange that can cause the limit to be exceeded. However, once exceeded, it can affect SharePoint users as well as Exchange users.
If you wish to use a NAT/NAPT device in front of users who are likely to access Nexus (Exchange and SharePoint), please register this device with the Nexus Team. Send the IP address(es) to email@example.com prefixing the subject line [ITSS] with a short explanation. Once the exception is created at the Nexus Threat Management Gateway your users' performance issues should be resolved.