Shimmer
From HacDC Wiki
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
- ./hovzNewUser <userName> # Creates user account with default Xen VM and permissions.
- ./hovzDelUser <userName> # Deletes user account, associated VMs, and associated Xen permissions.
- ./hovzNewVM <userName> <VM_Number> <dist> # Creates VM accessible to non-root user <userName> .
Autostart
Through normal reboots, host will suspend/resume any guest VMs.
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 --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 .
ReInstall
- Install OpenVZ, documented at http://openvz.org/Installation_on_Debian .
- Install hostedOpenVZ, documented at https://github.com/mirage335/hostedOpenVZ .
- Change default kernel in /etc/default/grub.cfg .
- Apply "iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE" .
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.
Special Services
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