What are the commands to generate a SYSLOG within ServPoET?
save/quit file – command line: wq
And restart syslog
And start listening and logging to stdout
tail -f /var/log/message
or to logfile
tail -f /var/log/message>log.txt
What is the maximum upper limit of ip_conntrack?
What are the commands to search for a subscriber within the ServPoET NOS?
find .|xargs grep ‘username’
Does ServPoET have a built-in SNMP agent? If so, what MIBs are supported?
The MIB is just the standard Linux 2.4 kernel MIB, SNMP is limited to read-only in the current version, but is under active development to support full read/write.
How do you change the settings for Ethernet Interfaces (i.e. speed, duplex, etc…)?
In order to change the settings for Ethernet Interfaces (i.e. speed, duplex, etc…), ‘auto-negotiation’ must be disabled in order for the changes to take in affect. For example:
1. ethtool -s eth0 autoneg off
2. ethtool -s eth0 duplex half
3. ethtool -s eth0 speed 10
4. ethtool -s eth0 autoneg on
If VLANs on the PPP interface are created, are any of the PPP Options affected?
When VLANs on the PPP interface are created the MTU setting in “Configure PPP Options” both Maximum transfer, and Maximum receive unit need to be no more than 1488, 4 bytes of header created by the VLAN and the 8 bytes created for the PPPoE header.
(ServPoET v3.5.0 and earlier) How does ServPoET handle multiple RADIUS servers?
Within ServPoET NOS v3.5.0 and earlier, if the NOS is configured with multiple RADIUS servers, the incoming PPPoE session with authenticate to only the newest RADIUS server entry added. Most ISP’s have multiple RADIUS servers listed for redundancey, so there is a known issue with the ServPoET NOS where the incoming PPPoE session is not properly routed. In order to address the issue, the following commands must be applied to ‘radiusclient.conf’
The RADIUS server listing must appear as follows:
1. vi /etc/sysconfig/gateways
2. Make sure the only like in that file is the default, delete the lines below it.
3. save the file
4. /etc/init.d/network restart
Then test with a PPPoE client, do not go back in to the rpconfig GUI.
authserver 192.168.0.206:1812, 192.168.0.205:1812
acctserver 192.168.0.206:1813, 192.168.0.205:1813
Then, you have to copy the file to another location to make the change permanent –
1. mount –rwo remount /roroot
2. cp /etc/ppp/radiusclient/radiusclient.conf /roroot/tree/etc/ppp/radiusclient/radiusclient.conf
3. mount -ro remount /roroot
How do you capture real time PPPoE activity on ServPoET?
There are 2 ways:
1. You can pipe tcpdump traffic to grep utility to filter out PPP packets. Within the Linux console type the following command: ‘tcpdump -vvv -i eth1 | grep -I ppp’. If you want to create a temp file, then this command comes handy: ‘tcpdump -vvv -i eth1 | grep -I ppp > /temp/dump’. ‘more /temp/dump’ can be used to open dump file. Here we assume that PPPoE connections are going through eth1 interface.
2. It requires a spare Linux box. You can configure remote logging to this Linux box in web or char GUI, then add word ‘debug’ to additional PPP settings (char or web PPP configuration screen), then stop syslog daemon: ‘/etc/init.d/syslogd stop’ on the Linux box and start it in remote mode: ‘syslogd -r’. You can use ‘tail -f /var/log/messages’ to see debug info that comes to this box from ServPoET.
How do you export configuration files from ServPoET?
Restoration procedures are as follows:
1. Archived the following MASTER configuration files
C: /etc/sysconfig/bridges [applicable 3.6.0 above]
D: /etc/sysconfig/bridgeslaves [applicable 3.6.0 above]
2. Restore the files
3. Run rpconfig with the following principle that ServPoET must recognize some changes in order to flush parameters into individual SLAVE configuration files from MASTER files above.
NOTE: The administrator must then run rpconfig and do a “change value, OK, change back, OK” process of a single parameter value in each of a subset of rpconfig screen that’s wide enough to cause ServPoET to update all slave configuration files from the master. This is necessary because there is currently no unified programmatical process to do this master-to-slave parameter value population outside of the as-necessary updates done by rpconfig. A particular minimum subset of screens that must be touched to ensure that all slave files have been updated, are as follows:
a. Configure Networks
b. Configure PPPoE Server
c. Configure Firewall
4. Reboot System
How do you bypass RADIUS authentication?
In order to bypass RADIUS authentication and to terminate the session locally, the following line must be added to ‘pppoe-server-options’:
ServPoET BMS [NOS @ServPoET]# vi /etc/ppp/pppoe-server-options
# PPP options for the PPPoE/LNS server
;#######add the following line#######
;#######in order to write to the file and quit#######
“/etc/ppp/pppoe-server-options” 16L, 366C written
Neighbor overflow issue – ‘operation not permitted’
1. Add the following line in /etc/sysctl.conf:
2. net.ipv4.neigh.default.gc_thresh3 = 4096
3. And then, run ‘sysctl -p’ to activate
Make the changes in sysctl.conf permanently.
1. edit /etc/sysctl.conf
2. mount –rwo remount /roroot
3. cp /etc/sysctl.conf /roroot/tree/etc/sysctl.conf
4. mount -ro remount /roroot
ServPoET NOS v3.x – Proxy ARP, cannot PING devices or new sessions
1. With a valid PPPoE connection established (client =server), at the command line of ServPoET type:
a. cd /proc/net/ (enter)
b. arp -e (enter)
2. Command will show the current ARP table
3. You should not see an entry for the customer connected
4. Once confirmed that no entry exists, on the client, browse to a website to establish Internet traffic
5. After you successfully established a connection to an online website, repeat step #1:
6. With a valid PPPoE connection established (client =server), at the command line of ServPoET type:
a. cd /proc/net/ (enter)
b. arp -e (enter)
7. Command will show the current ARP table
8. You should now see an ARP entry for the MAC address of the customer
a. NOTE: When Proxy ARP is disabled, you will not see an ARP entry for the customer even after the client is connected to an online website
In order to resolve the issue permanently, follow the steps below:
1. Edit: /etc/sysctl.conf
2. Add the following line:
a. net/ipv4/conf/all/proxy_arp = 1
3. Run ‘sysctl –p’ to activate
4. Make the changes in sysctl.conf permanently.
a. edit /etc/sysctl.conf
b. mount -rwo remount /roroot
c. cp /etc/sysctl.conf /roroot/tree/etc/sysctl.conf
d. mount -ro remount /roroot