Cisco 2821 Router as a NTP Server

We are using a 2821 Router as our boundary router. It has installed into it a 9 port HWIC for layer 2 switching as well as allowing the router to communicate on the Network Management VLAN. All of the devices on the Network Management VLAN are segregated from the managed traffic, which unfortunately also doesn't allow them external NTP services. Can the router be programmed as a NTP server so that all of the network appliances can utilize it for NTP from either it's NM Vlan IP address or from a loopback address? Thanks in advance for the help.

What are the commands needed in the router for it to provide time to other appliances?
If your router has successfully synchronized with an authoritative NTP server? NOT A THING.
In my network, only the site's distribution switch is allowed to go out and get NTP. All other access switch goes to the distribution switch by using the command "ntp server ". You can have multiple NTP server IP address and if you prefer to have a "favorite" you can append your command with the "prefer" option: ntp server prefer.
If you have clients then point their NTP to your router. For troubleshooting, I prefer the command "sh ntp associate". If your NTP server IP address starts with a "*" this is good and means that your NTP is synchronized.
Hope this answers your question.

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How to view Log on the cisco 2821 Router

Hi,
can any one help me to view the Log on the Cisco 2821 router for any issue occur.
Thanks,
Saroj

Cisco devices use the syslog to manage system logs and alerts. But in Cisco devices there is lack of large internal storage space for storing these kinds of logs.So to overcome Cisco devices has the following two options:
1) internanal buffer — That is a small part of memory buffers to collect log the most recent messages. The buffer size is limited and , when the device reboots, these syslog messages are lost.by default it is on
(If not follow this steps
conf t
logging on
logging console.....console logs
logging buffer size ......set the size of buffer
terminal monitor.......to gets logs on the remote terminal like telnet,ssh etc.
sh logging.........to see buffer logs.)
2) Syslog server— By using this we can send messages to an external device for storing this logs and the storage size does depend on the available disk space of the external syslog server. This option is not enabled by default.
If you have any syslog server please find the below simple config .
conf t
logging host x.x.x.x
logging traps (i.e 0 1 2 3 4 5 .. according to your requirement)
before enabling logging be sure that your router is properly configure to collect proper time from any NTP server or manually configure to get time
command to set time manually on router is (set clock ) or to use ntp server use ntp server x.x.x.x to sync clock to router router.
Hop thant is informative ,
Regards,
Ashish

Cisco 2821 router won't keep config

Hi
I have a cisco 2821 router that i'm trying to load a config on and for some reason it will not stay once i reboot it.
I can get the config on and give it a host name and everything that i need but when i reboot it goes back to
router> as the host name and no config on it.What would be causing this problem as this is my first time seeing
this before and thanks for your help in advance.

Check your config-registry using the "sh version" command. It should be 0x2102 and you can change this using the command "config-registry 0x2102" and a reboot.

Connecting Cisco 2821 Router, Switch, and Cable Modem

Hey everyone,
I am currently in the Cisco Network Academy at my school and just finished CCNA 1. I have a few questions though.
I am purchasing new equipment and that equipment includes:
1-Cisco 2821 2-port Gigabit Router
1-Linksys SE3016 16-Port Gigabit Switch (unmanaged)
1-Cisco WAP4410n Wireless Access Point
1-Motorla SurfBoard Gigabit Cable Modem (no router built in-Just standalone Modem used with Comcast Xfinity High Speed Internet)
1-12U Network Rack (not enclosed)
I am confused on how I will connect the cable modem to the router and the router to the switch and the WAP so that I still have WiFi. Since the router only has 2 Ge Ports, how would I cable this up?
If my assumptions are correct, would I do the following set up?
Take the Cable Modem and run a Straight Thru to Port 1 of the Router.
Connect the Switch Port 1 to Port 2 of the Router using a Straight Thru cable (I believe I will most likely have to Subnet a network, won't I?).
Connect Switch Port 2 to WAP using Straight Thru Cable (so I still have WiFi in my home).
Connect all my computers and other devices to the Switch (this includes several PC's/Laptops, two printers that are ethernet, two TV's that are ethernet, an AppleTV and a Blue Ray Player that are both ethernet, and some Cisco Powerline Network Adapters).
Will that set up work?
Also, how would I configure the router to work with my cable modem AND act as a DHCP Server so that all of my devices get IP Addresses? I have the Cisco Command Guide Book, but it is confusing to me as of now.
Thanks!
Chris

A good start but a few points I would make.
If you set the clock manually, you may find it resets itself after a router reboot. I would look at pointing it at an NTP server:
#ntp server x.x.x.x
#clock timezone GMT (Assuming you are UK based)
Although not required, I would put a description on each of the interfaces as it may help identify them later if you are not physically in front of the Router.
#interface gi0/0
#description WAN
Same for LAN
You have set up your LAN subnet with a /16 subnet mask which is effectively 10.0.0.1 - 10.0.255.254. This is a large subnet allowing over 65k hosts which is not best practice on enterprise networks. It probably won't cause you any issues but I doubt you will have any more than 254 hosts so personally I would use a /24 subnet (255.255.255.0)
The only major thing missing is NAT which needs to be configured on the router to translate the LAN IP addresses from their 10.* private range to the Public IP address on the Gi0/0 WAN Interface.
Firstly you need to define the 'inside' and 'outside' NAT interfaces which is fairly self explanatory:
#interface gi0/0
#ip nat outside
#interface gi0/1
#ip nat inside
Gi0/0 is your outside interface because its facing the Outside world (i.e the internet) and Gi0/1 is your inside interface because its facing Inside your LAN.
Then you need to tell the router which addresses to translate against by first creating an access list:
#ip access-list standard LAN-Addresses
#permit 10.0.0.0 0.0.255.255
Finally you need to tell the router to start translating:
#ip nat inside source list LAN-Addresses interface gi0/0 overload
Oh, I have just noticed that you do not have a 'default route' configured. A router forwards packets by first looking up the destination IP address of the packet (i.e where its going) in it's own routing table. Obviously home routers are not going to have an entry for every Public IP subnet on the internet so they use something called a default route which effectively says 'If I cannot find an entry for this packet in my routing table, use the default route'.
As you are on DHCP and your IP address (and even default gateway) could change on your WAN interface, I would not bother with the next hop address in the default route but rather use the outgoing interface as below:
#ip route 0.0.0.0 0.0.0.0 gi0/0
Hope this helps!

Traffic Shaping on Cisco 2821 router

I have two sites and connected with MPLS links of 2MB with Cisco 2821 routers. Now a requirement came that two sites will have additional server ( one each location - for data replication purpose) and 75% of the bandwidth needs to be allocated to data replication servers on each site and rest of 25% bandwidth will be utilize for both sides normal traffic.
Is there any additional modules to be added on each router to isolate the traffic. Please let me know.
Thanks,

To expand on the information that Collin provided . . .
If you really want to cap the bandwidth to a class of traffic, i.e. truly limit replication to 75%, you can add a policer or shaper to a class, similar to what Collin shows.
e.g.
policy-map RestrictAltiris
class Altiris
bandwidth percent 20
shape average 1500000
However, like Collin, since CBWFQ guarantees bandwidth allocations, you rarely need to cap bandwidth if you, for instance, insure your other traffic gets the other 25% (i.e. 100% less 75% for replication).
e.g.
policy-map RestrictAltiris
class Altiris
bandwidth percent 75
(NB: BTW, there are other rules pertaining to bandwidth reservations, but prior examples, both Collin's and mine, should suffice.)
Also BTW, since you mention MPLS, and since MPLS often allows multisite communication, if there are more than just these two sites that can communicate with these two sites across their 2 Mbps links, other considerations apply for dealing with such a situation.
PS:
Although software based QoS should meet your stated requirements, there are optional modules to provide "WAN optimization", see http://www.cisco.com/en/US/prod/collateral/contnetw/ps5680/ps6870/product_data_sheet0900aecd8058218c.html.
PPS:
BTW, when Collin describes:
". . . but when the link gets congested the router will limit the traffic for this host to 20% of the total interface bandwidth, and all the remaining traffic to 80%.", this might be just a bit misleading since when the link is congested individual classes aren't really limited they are instead guaranteed their bandwidths as a minimum, not precisely the same thing. For example with 20% and 80% guarantees, either class could still obtain unused bandwidth from the other class while the link is congested.
[edit]
This being true, for something like what you describe, I would recommend using the least amount of bandwidth guarantee that data replication needs. Assuming your other traffic, on average, doesn't consume more than 25% of the bandwidth, you might find even providing replication only 1% for a bandwidth guarantee works fine. Why you would want to do this, by lowering the bandwidth guarantee for replication, you allow other traffic to burst. Such bursting capability normally improves any kind of transactional or conversational applications and doesn't (usually) unduly delay replication.

Cisco 3750X wont sync to ntp server

sh version
Switch Ports Model SW Version SW Image
* 1 30 WS-C3750X-24 15.0(2)SE5 C3750E-UNIVERSALK9-M
nsi.swcore01#sho ntp associations
address ref clock st when poll reach delay offset disp
~192.168.68.254 .INIT. 16 - 1024 0 0.000 0.000 15937.
* sys.peer, # selected, + candidate, - outlyer, x falseticker, ~ configured
nsi.swcore01#sh ntp status
Clock is unsynchronized, stratum 16, no reference clock
nominal freq is 119.2092 Hz, actual freq is 119.2092 Hz, precision is 2**17
reference time is 00000000.00000000 (08:00:00.000 GMT Mon Jan 1 1900)
clock offset is 0.0000 msec, root delay is 0.00 msec
root dispersion is 46985.14 msec, peer dispersion is 0.00 msec
loopfilter state is 'FSET' (Drift set from file), drift is 0.000000000 s/s
system poll interval is 64, never updated.
I tried to manually set the time so that the ntp server and the switch will have almost identical time, and btw NTP Server is a firewall, IP of the switch is allowed, and im actually seeing logs on the firewall side(watchguard) that it is trying to sync w/ the ntp server

NTP server is watchguard firewall, other devices such as AD, ubuntu server is pointed on it and using its time sychronization and its working, i dont know why im having an issue w/ cisco 3750x

Is Cisco 2821 Router a Fax gateway?

Hi experts,
I have 2811 router with pvdm2 card on it. I want to know if it is possible to configure 2811 as a fax gateway.
Thank you

What are the commands needed in the router for it to provide time to other appliances?
If your router has successfully synchronized with an authoritative NTP server? NOT A THING.
In my network, only the site's distribution switch is allowed to go out and get NTP. All other access switch goes to the distribution switch by using the command "ntp server ". You can have multiple NTP server IP address and if you prefer to have a "favorite" you can append your command with the "prefer" option: ntp server prefer.
If you have clients then point their NTP to your router. For troubleshooting, I prefer the command "sh ntp associate". If your NTP server IP address starts with a "*" this is good and means that your NTP is synchronized.
Hope this answers your question.

Cisco 2821 router IOS and Ipsec

Hi all.I was wondering can you create VPN tunnels using Ipsec on a 2821 router if you have only the IPBASE image(the basic image 2821 router comes with) on the router or do you need some other version of IOS?
I've gone totally nuts trying to find out but can't seem to find an answer.Thanks in advance.

Igor
You can not create IPSec tunnels if the 2821 is running the IP BASE image. You need a feature set that supports crypto to do IPSec. In general image names that include k9 in the image name will support crypto. You probably would want the Advanced Security feature set or the Advanced IP Services feature set, both of which do support crypto and do support IPSec tunnels.
HTH
Rick

Linux ntp server with cisco 3850

hi all
i'm trying to make sync with linux ntp with cisco 3850 here is the what i did
linux centos 6.5 (on the ucs virtual machin) . this is a ntp server
ip 10.1.1.251
===================================================
For more information about this file, see the man pages
# ntp.conf(5), ntp_acc(5), ntp_auth(5), ntp_clock(5), ntp_misc(5), ntp_mon(5).
driftfile /var/lib/ntp/drift
# Permit time synchronization with our time source, but do not
# permit the source to query or modify the service on this system.
restrict default kod nomodify notrap nopeer noquery
restrict -6 default kod nomodify notrap nopeer noquery
# Permit all access over the loopback interface. This could
# be tightened as well, but to do so would effect some of
# the administrative functions.
restrict 127.0.0.1
restrict -6 ::1
# Hosts on local network are less restricted.
restrict 10.1.1.0 mask 255.255.255.0 nomodify notrap
# Use public servers from the pool.ntp.org project.
# Please consider joining the pool (http://www.pool.ntp.org/join.html)
#server 1.centos.pool.ntp.org iburs
#server 2.centos.pool.ntp.org iburst
#server 3.centos.pool.ntp.org iburst
server 127.127.1.0
fudge 127.127.1.0 stratum 2
#broadcast 192.168.1.255 autokey        # broadcast server
#broadcastclient                        # broadcast client
#broadcast 224.0.1.1 autokey            # multicast server
#multicastclient 224.0.1.1              # multicast client
#manycastserver 239.255.254.254         # manycast server
#manycastclient 239.255.254.254 autokey # manycast client
# Enable public key cryptography.
#crypto
includefile /etc/ntp/crypto/pw
# Key file containing the keys and key identifiers used when operating
# with symmetric key cryptography.
keys /etc/ntp/keys
# Specify the key identifiers which are trusted.
#trustedkey 4 8 42
# Specify the key identifier to use with the ntpdc utility.
#requestkey 8
# Specify the key identifier to use with the ntpq utility.
#controlkey 8
# Enable writing of statistics records.
#statistics clockstats cryptostats loopstats peerstats
and cisco 3850 configured this one
ntp server 10.1.1.241
and
show ntp status
clock is unsynchronized, stratum 16, reference is null
why...didn't work.. somebody help me..

Is there a typo in your post or configuration? You show the NTP server IP address as 10.1.1.251, but the router configured to use 10.1.1.241.
Regards

Turn Cisco 877 Router into RADIUS Server?

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Peter

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Thanks

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Configuring lines 1 60 on Cisco 2821

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When I try to enter the line "router(config)#line 1 60" the ios returns an error message that there are no physical hardware to support "line 2". I just can enter line 1.
Which is necessary to do this?
My best Regards,
Adriano

try to do a show of the interface using the following example and see the output.
#sh voice po 1/1

Need reference of CCME on cisco 2821

Hello;
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What is the reference (to purchase) of the CCME software with 40 users license for the router cisco2821-sec/k9
The IP phone CP-521SG and CP-524SG can operate with a CCME installed on the Cisco 2821?
If not what kinds of the most cheap cisco IP phone can operate with a CCME installed on the Cisco 2821 router
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/* Style Definitions */
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mso-tstyle-rowband-size:0;
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Finally I choose to buy this element in the table
I already have the router cisco2821-sec/k9 and one cisco switch poe
Please the system will work or do I need additional requirement ?
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mso-tstyle-rowband-size:0;
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Reference
Quantity
FL-CCME-48
01
VIC2-4FXO
01
7945G
05
7911G
25

VOIP Card on Cisco 2821

Hi,
I want to set up a VOIP environment in my company. The topology is like this:
PBX1-75xx-WAN-2821-PBX2-phone
PBX2 is a panasonic TD88 Model.
The dial plan will be (from phone-set):
1.dial 8 for PSTN access direct to PBX2
2.dial 9 for accessing branch office under PBX1.
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Thanks
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Thanks
Joey

Cisco 2821 Router as a NTP Server

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