Shimmer
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(Redirected from HacDC-shared-m335-1)
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.
For discussion purposes, server is nicknamed "Shimmer".
ChiefAdmin
mirage335
Support
#hacdc on irc.freenode.net (or via chat.hacdc.org)
Login
On any unix terminal emulator, enter the command:
ssh <userName>@shimmer.srv.hacdc.org -p 2221
On other platforms, try applications like PuTTY with similar settings. Please use 192.168.14.254 for internal use.
CommandReference
Routinely important commands unique to this server documented as follows.
Users
List
List OpenVZ VMs created for you.
cat ~/hovzList
Startup
sudo /usr/sbin/vzctl start <name>
Shutdown
sudo /usr/sbin/vzctl stop <name>
Console
Opens command line of running VM <name> .
sudo /usr/sbin/vzctl enter <name>
Root (Admin)
hostedOpenVZ
- ./hovzNewUser <userName> # Creates user account with default OpenVZ VM and permissions.
- ./hovzDelUser <userName> # Deletes user account, associated VMs, and associated OpenVZ permissions.
- ./hovzNewVM <userName> <VM_Number> <dist> # Creates VM accessible to non-root user <userName> . Dist is often"debian-7.0-x86_64-minimal" .
- vzctl set CTID --ram 128M --swap 256M --save
- vzctl set CTID --diskspace 4G:4.2G --save
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
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" .
Characteristics
- CPU - E2200 Dual-Core 2.2GHz
- RAM - 4GB
- 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 OpenVZ VMs.
OpenVZ
All HacDC members are welcome to OpenVZ 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 hostedOpenVZ 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).
Forwarding to another email address is possible with the following command.
echo '[email protected]' > ~/.forward
Removal
- Up to 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
Disk
Disk space is limited, but can be upgraded. Please do not needlessly use more than a few tens of GB.
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
Although HacDC has a high-capacity 175/15Mbit link, it is shared with other tenants. Please be courteous. If internet bandwidth use is required for downloading large files, between 2200 and 0600 is best.
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.
- NOTE: If your bandwidth use is too high during normal hours, the church administrator will cut bandwidth available to the whole subnet and will call mirage335, juri_, or other admin team members to resolve the issue (no one will be happy).
Special Services
HTTP/HTTPs
Ports 80/443 are available through reverse proxy. Please setup a relevant domain name (eg. *.member.hacdc.org) through FreeDNS or other service, and contact the HacDC admin team for assistance.
Funtoo
Funtoo (enhanced Gentoo) build server is available, with binary packages and weekly full-os tarballs for new installations.
After obtaining the password for remote access, upload a key and set PORTAGE_BINHOST="ssh://[email protected]:<port>/opt/mirage335OS-x64/usr/portage/packages" .
ssh-copy-id -i "./key.pub [email protected] -p 24789
This also provides access to regularly generated tarball images for re/installation of a fresh OS.
Softload
https://github.com/mirage335/hostedOpenVZ
NamingConvention
Preferred network names for participating machines and virtual machines.
Physical
Hostnames
HacDC-shared-m335-1
- HacDC - Identifies machine as HacDC or HacDC member property on the local network.
- shared - One of private, restricted, shared. Private = one member only (eg. RasPi). Restricted = limited access (eg. HacDC web server). Shared = shared resources (ie. remote shells).
- m335 - Abbreviated member name or screen name. Full contact details should be written on the physical machine.
- 1 - Unique identifier.
FQDNs
HacDC-shared-m335-1.router.hacdc.org
Virtual
Hostnames
mirage335-1
- mirage335 - Local username.
- 1 - Unique machine identifier.
FQDNs
mirage335-1.HacDC-shared-m335-1.router.hacdc.org
Timezone
EST/EDT aka US Eastern, America/NewYork, or "Eastern"
Workarounds
SSH KeepAlive
Due to limited bandwidth, SSH sessions may freeze. To prevent this, consider the following to configuration, appended to client-side ~/.ssh/config .
Host * ServerAliveInterval 30
Disclaimer
No guarantees. Admins are expected to make best efforts toward reliability, security, and privacy. Monitoring may include without limitation system health, resource consumption, and authentication failures, and the like. More intrusive monitoring, such as of user filesystems, should be avoided if possible.
Credits
Hunterkll - Donated core hardware.
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