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Mailserver upgrade

The new file and mail server is cech05. Mails can be accessed as usual using IMAP (TLS/SSL), POP3/POP3s or via SSH-login and the standard unix tools (pine, mutt, mail). Plain IMAP (i.e., without encryption) is not supported anymore. In addition to the options above there is a webmail interface (using IMAP as its backend) that is accessible world wide and that allows for sending mail from remote.
IMAP users (or users switching to IMAP) may access their whole IMAP folder system through this webmail interface (you have to subscribe to the appropriate folders there) as long as these folders are residing on the server. For local access (i.e. from the Institute) you should use direct IMAP in preference to the webmail interface for performance reasons.
Further, all home directories can be accessed through samba and may be mounted as a network share for storage of important data (will be included in the central backup at ZIH).

Usage help


(discouraged; use IMAP instead).

For accessing mail via POP3 the only settings to be changed are the hostnames of the incoming and outgoing mail servers (replace cech04 with cech05). Usernames and passwords remained unchanged. Parallel access from different mail profiles to both machines (cech04 and cech05) simultaneously is strongly discouraged; there is only one NFS-shared file system (physically held at cech05), so inconsistencies (loss of mails in the worst case, that is) cannot be excluded.

Configuration dialog of mail reader (POP3/POP3s):
Incoming Mailserver
POP3-Server: cech05.chm.tu-dresden.de
POP3-Port: 110 (995 in case of encryption via POP3s aka POP3-SSL*)
POP3-Username: username as usual
POP3-Password: password as usual
Secure authentication:No**
Outgoing Mailserver
* Usually the port number will change automatically when "Encryption" is selected in the dialog box
** You must specify "No" here, CRAM-MD5-Authentification is unsupported. Ironically, it would be less secure than password authentication via an encrypted channel, anyway.

Note: Access from outside the institue should always use encrypted communication; for internal access this is not necessary (performance).


The same as above generally also holds for IMAP access, the main difference being that unencrypted IMAP connections are not longer supported (server limitation). In general there are two possible ways to negotiate an encrypted connection, one is via IMAP-TLS (sometimes also referred to as STARTTLS, preferred option) and the second one is IMAP-SSL. So there are two options to choose from that just differ in their destination port and connection protocol. Most modern mail readers (PMail aka Pegasus Mail, Thunderbird, Mozilla, Opera, ...) will correctly handle both options without a problem, only Outlook (and Outlook Express) are violating the standards (as usual) and cannot correctly handle option 1 (IMAP-TLS), so there's only option 2 (IMAP-SSL) available. You may also consider changing your mail reader, what would be a benefit anyway and is strongly recommended, since the inseparable "duo infernale" Outlook Express + Internet Explorer was (and still is) the major intrusion channel for malware of any kind.

Configuration dialog of mail reader (IMAP/IMAPs):
Incoming Mailserver
IMAP-Server: cech05.chm.tu-dresden.de
   Option 1: TLS (STARTTLS)
IMAP-Port: 143
Encryption: TLS (always, not only "if available")
   Option 2: SSL
IMAP-Port: 993*
Encryption: SSL
   Both options
IMAP-Username: username as usual
IMAP-Password: password as usual
Secure authentication:No**
Outgoing Mailserver
SMTP-Server: cech05.chm.tu-dresden.de
SMTP-Port: 25
* same footnote as above. Encryption here: SSL.
** cf. footnote two above


The webmail interface can be accessed world wide at https://cech05.chm.tu-dresden.de/. In case you specify http:// there will be an automated redirection to https, so the connection will always be encrypted. There will also be a link from our insitute web pages.
To "see" all your private IMAP folders besides the standard ones (INBOX, Trash & Co) you'll have to "subscribe" to these folders, as is the usual way using IMAP.

Samba/Network shares

Accessing your home directory as a network share using samba is trivially easy. In Windows explorer, choose "Extras -> Connect network share", enter \\cech05\username as the destination path on the server (sometimes also referred to as folder) and supply your credentials when asked to authenticate yourself.
Note:For connecting to the network share service your password data had to be synchronised already. This will happen after at least one successful login through one of the other services, i.e. POP, IMAP, webmail or an SSH shell login.

Quota and warning mails

User's HOME directories and mail INBOXes reside on physically different file systems with different storage capacities. For several reasons these file systems have quotas enabled, i.e. users can use only a limited amount of storage space. The limits are usually 512MB-1GB for mail INBOXes and more than 5GB for user's HOME directories.

The system is performing quota checks once per day, and will issue a warning email (Subject: Over quota...) in case the soft limits were exceeded. Take these mails seriously, as after a certain grace period (usually 7 days) you won't be able to receive any mails at all (actually, the mails will be rejected!).

Remedy: Besides the obvious clean-up of your mail INBOX (delete mails, that is) there is also the possiblity to move mails to a different IMAP mail folder. These folders reside on the HOME file system with significantly larger storage capacity than INBOX. To create such an additional mail folder, you usually have to richt-click on the mail account (Thunderbird & Co) and select "Create (sub-)folder". These newly created IMAP folders will automatically be subscribed to.

Important: In both cases (delete and move mails) you'll have to "compact" the INBOX folder afterwards, otherwise mails will only be tagged, not removed from INBOX. In order to do so just richt-click on INBOX, then choose "Compact this folder" (or similar) from the popup context menu. Done.



AK Eychmüller, AK Mertig
Tel.: +49 351 463 37597
Fax: +49 351 463 37164
E-Mail: pc@chemie.tu-dresden.de

Bergstraße 66b
Raum 101

TU Dresden
Fakultät Chemie und Lebensmittelchemie
Physikalische Chemie
01062 Dresden

AK Seifert, AK Weidinger
Tel.: +49 351 463 34467
Fax: +49 351 463 35953
E-Mail: pc@chemie.tu-dresden.de

Bergstraße 66c
Raum 107

TU Dresden
Fakultät Chemie und Lebensmittelchemie
Theoretische Chemie
01062 Dresden