Shimmer

Simple project server, emphasis on availability and uptime.

Most likely, this server will continue operating for several years, even as newer and better servers supplant it.

Login

On any unix terminal emulator, enter the command:

ssh <userName>@HacDC-shared-m335-1.hacdc.org

On other platforms, try applications like PuTTY with similar settings.

CommandReference

Routinely important commands unique to this server documented as follows.

Root (Admin)

hostedXen

• ./hxNewUser <userName> # Creates user account with default Xen VM and permissions.
• ./hxDelUser <userName> # Deletes user account, associated VMs, and associated Xen permissions.
• ./hxNewVM <userName> <VM_Number> <dist> # Creates VM accessible to non-root user <userName> .

Autostart

Through normal reboots, host will suspend/resume any guest VMs. If that is insufficient, the correct way to enable autostarting is through the xm command, documented as method 2 here.

iptables

Investigation

• iptables -t nat -L -n -v #Lists port forwarding rules.
• iptables -t nat -F #Deletes port forwarding rules.
• iptables -D PREROUTING 1 #Deletes port forwarding rule.

Forwarding

Enable

/sbin/iptables -P FORWARD ACCEPT
/sbin/iptables --table nat -A POSTROUTING -o eth0 -j MASQUERADE

Specific

/sbin/iptables -t nat -A PREROUTING -p tcp -i eth0 --dport 20283 -j DNAT --to 10.174.10.5:22

Persistent

Package iptables-persistent has been installed. Upon installation, existing iptables rules were saved. Edit /etc/iptables/rules.v4 .

Users

List

List Xen VMs created for you.

cat ~/xenList

Startup

Start Xen VM, and launch console.

sudo /usr/sbin/xm create -c /etc/xen/<name>.cfg     #Escape with Ctrl+] .

Just start Xen VM. Useful if planning to interact through other means (ie. network).

sudo /usr/sbin/xm create /etc/xen/<name>.cfg

Shutdown

Yes, really, hard shutdown is termed "destroy". Don't worry, not synonymous with "delete".

sudo /usr/sbin/xm destroy <name>

Console

Opens the console of running VM <name> .

sudo /usr/sbin/xm console <name>     #Escape with Ctrl+] .

Characteristics

• CPU - E2200 Dual-Core 2.2GHz
• RAM - 1GB
• HDD - 500GB
• Hostname - HacDC-shared-m335-1
• FQDN - HacDC-shared-m335-1.hacdc.org

Redundancy (RAID)

None yet, keep backups. Nonetheless, hard disk is kept cool, so the server should have a long life ahead of it.

Policies

Permissions

Root

HacDC members with a demonstrable need or willingness to manage non-root users may be given root access. Imperative that root users do not jeopardize uptime.

Shell

All HacDC members are welcome to non-root shell accounts, directly provided by the server, and used to manage Xen VMs.

Xen

All HacDC members are welcome to Xen Virtual Machines. Resources, including CPU, disk space, and external network ports, will be allocated on an as-needed first-come-first-serve basis.

Root users, please use the provided hostedXen scripts. Following the naming conventions set therein helps account for which resources belong to whom.

Notifications

Internal server email will notify users, if feasible, on the following schedules, subject to change.

• Three days before planned downtime exceeding one hour.
• One week before planned permanent downtime (obsolescence).

Removal

• Three months before removal of ex-member accounts. Exceptions on a case-by-case basis.

DataLoss

• Users should regularly backup critical data offiste.
• Onsite data storage is not guaranteed to be reliable.
• All server data may be deleted after obsolescence.
• Removed accounts may be deleted immediately and permanently upon deactivation.

Privacy

Machine is physically accessible to all keyholding HacDC members. Although HacDC members are generally responsible, privacy should not be expected.

AcceptableUse

Sharing

Sharing of account resources is permitted, however, additional resources will be allocated according to individual member needs for specific purposes. As a reminder, compromised accounts will be immediately removed as discovered.

Bandwidth

Hard bandwidth limits have not been set to ease administration of local file servers. However, please configure applications to limit maximum bandwidth use where possible, particularly for web servers.

ChiefAdmin

mirage335

Credits

Hunterkll - Donated core hardware.

Funtoo

Funtoo (enhanced Gentoo) build server is available, with binary packages and weekly full-os tarballs for new installations.

Softload

https://github.com/mirage335/hostedXen

Reference

• https://wiki.debian.org/Xen#Domain_0_.28Host.29_Installation
• http://dev.e-taxonomy.eu/trac/wiki/Xen_installation
• http://wiki.xenproject.org/wiki/Nested_Virtualization_in_Xen#How_to_use_nested
• http://wiki.xen.org/wiki/Host_Configuration/Networking#Routing
• http://blog.manula.org/2012/04/manually-configuring-nat-networking-in.html
• http://www.fclose.com/816/port-forwarding-using-iptables/
• https://wiki.debian.org/iptables
• http://blog.manula.org/2011/02/xen-bridged-networking-mode.html
• http://xen.1045712.n5.nabble.com/console-access-to-non-root-xen-3-0-td2560667.html
• http://xen-tools.org/pipermail/xen-tools-discuss/2009-September/000674.html
• https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/5/html/Virtualization/sect-Virtualization-Tips_and_tricks-Limit_network_bandwidth_for_a_Xen_guest.html
• http://serverfault.com/questions/52027/how-can-i-limit-per-user-bandwidth
• http://www.howtoforge.com/nat-gateway-iptables-port-forwarding-dns-and-dhcp-setup-ubuntu-8.10-server
• https://major.io/2007/02/09/delete-single-iptables-rules/
• https://www.novell.com/support/kb/doc.php?id=3466408

HacDC-shared-m335-1_Xen