SRST for SIP and SCCP IP phone over same GW at the same time

[SNB]

Hi,

Has anyone try to configure SRST for SCCP and SIP phones on the same GW and to make it works at same time?
Does anyone know whether it is possible?

I have a CISCO 2921 router; when GW goes into SRST mode, SIP phones register propely, but SCCP phones seems to do nothing (not even a single SCCP message arrive to the GW from the phones).

I have checkd SRTS config on GW and CUCM many time, I don't think it's a config issue.

Thanks a lot!

[SNB]

Hi,

Has anyone try to configure SRST for SCCP and SIP phones on the same GW and to make it works at same time?
Does anyone know whether it is possible?

I have a CISCO 2921 router; when GW goes into SRST mode, SIP phones register propely, but SCCP phones seems to do nothing (not even a single SCCP message arrive to the GW from the phones).

I have checkd SRTS config on GW and CUCM many time, I don't think it's a config issue.

Thanks a lot!

[Jaime Valencia]

Yes, both can be configured in the same ISR 

[SNB]

Gracias Jaime!

Yes, both can be indeed.

But, once the router comes into SRST mode, will SIP and SCCP phones get properly resgistered?

I've tried with two different routers and I got only SCCP or SIP registered on SRST.

It looks like the router falls into SRST mode for SCCP or SIP, but not the two protocols at the same time.

Kind regards,

SNB.

[Roger Kallberg]

This definitely works for both protocols at the same time. Could you please post the configuration you have so that we can verify it?

[SNB]

Hi,

This is the configuration.

SIP phones registered properly on SRST GW. SCCP did not.

"Debug sccp all" dis not show nothing at all from the IP Phones.
Between IP Phones and GW there's only a switch (niether router, nor FW).

##########################################################

card type e1 0 0

clock timezone cet 1 0
clock summer-time cet recurring last Sun Mar 2:00 last Sun Oct 3:00
network-clock-participate wic 0
!

!
ip dhcp pool VOICE
network 10.95.159.0 255.255.255.128
default-router 10.95.159.6
option 150 ip 10.232.5.20 10.232.5.21

no ip igmp snooping

!
stcapp ccm-group 1
stcapp
!
stcapp feature access-code
!
stcapp feature speed-dial
!
!
!
stcapp supplementary-services
port 0/2/0
fallback-dn 259238
port 0/2/1
fallback-dn 259237
port 0/2/2
fallback-dn 259234
port 0/2/3
fallback-dn 259226
port 0/3/0
fallback-dn 259239
port 0/3/1
fallback-dn 259229
port 0/3/2
fallback-dn 259235
port 0/3/3
fallback-dn 259240
!
!
isdn switch-type primary-net5

!
voice-card 0
!
!
!
voice service voip
allow-connections sip to sip
fax protocol t38 version 0 ls-redundancy 0 hs-redundancy 0 fallback none
sip
bind control source-interface GigabitEthernet0/0
bind media source-interface GigabitEthernet0/0
registrar server expires max 600 min 60
!
!
!
!
voice register global
default mode
no allow-hash-in-dn
system message primary CCM caido, SRST activado
max-dn 100
max-pool 42
!
voice register pool 1
id network 10.95.159.0 mask 255.255.255.128 <<<< DHCP Voice Network for IP Phones
dtmf-relay rtp-nte sip-kpml
codec g711ulaw
!
!
!
voice translation-rule 1
rule 1 /.*/ /259200/
!
!
voice translation-profile PSTN-IN
translate called 1
!
!
!
!
application
global
service alternate default
!

hw-module pvdm 0/0
!
!
!

!
controller E1 0/0/0
pri-group timeslots 1-31 service mgcp
no cdp run
!

!
interface Loopback10
description Managemenet
ip address 10.199.249.238 255.255.255.255
!
interface Loopback200
ip address 10.199.226.31 255.255.255.255
!
interface Embedded-Service-Engine0/0
no ip address
shutdown
!
interface GigabitEthernet0/0
description Interface LAN Cliente
ip address 10.95.159.6 255.255.255.128
no ip redirects
no ip proxy-arp
ip virtual-reassembly in
ip tcp adjust-mss 1350
duplex auto
speed auto
!
interface GigabitEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
interface GigabitEthernet0/2
no ip address
shutdown
duplex auto
speed auto
!
interface Serial0/0/0:15
no ip address
encapsulation hdlc
no cdp enable
isdn switch-type primary-net5
isdn incoming-voice voice
isdn bind-l3 ccm-manager
isdn bchan-number-order ascending
!

access-list 199 permit ip 10.232.5.0 0.0.0.15 host 10.95.159.6 <<<<< Access-list used to tear down connection to CUCM
access-list 199 permit ip 10.232.5.0 0.0.0.15 host 10.199.226.31
access-list 199 permit ip 10.95.159.0 0.0.0.127 host 10.95.159.6
!
!
!
control-plane
!
call fallback active
!
voice-port 0/0/0:15
translation-profile incoming PSTN-IN
cptone PL
!
voice-port 0/1/0
no battery-reversal
cptone PL
timing hookflash-out 50
timing guard-out 1000
connection plar 259200
caller-id enable
!
voice-port 0/1/1
no battery-reversal
cptone PL
timing hookflash-out 50
timing guard-out 1000
connection plar 259200
caller-id enable
!
voice-port 0/2/0
cptone PL
timeouts ringing infinity
!
voice-port 0/2/1
cptone PL
timeouts ringing infinity
!
voice-port 0/2/2
timeouts ringing infinity
!
voice-port 0/2/3
timeouts ringing infinity
!
voice-port 0/3/0
timeouts ringing infinity
!
voice-port 0/3/1
timeouts ringing infinity
!
voice-port 0/3/2
timeouts ringing infinity
!
voice-port 0/3/3
timeouts ringing infinity
!
!
!
!
!
mgcp
mgcp call-agent 10.232.5.21 2427 service-type mgcp version 0.1
mgcp rtp unreachable timeout 1000 action notify
mgcp modem passthrough voip mode nse
mgcp package-capability rtp-package
mgcp package-capability sst-package
mgcp package-capability pre-package
no mgcp package-capability res-package
no mgcp timer receive-rtcp
mgcp sdp simple
mgcp fax t38 inhibit
mgcp rtp payload-type g726r16 static
mgcp bind control source-interface GigabitEthernet0/0
mgcp bind media source-interface GigabitEthernet0/0
mgcp behavior rsip-range tgcp-only
mgcp behavior comedia-role none
mgcp behavior comedia-check-media-src disable
mgcp behavior comedia-sdp-force disable
!
mgcp profile default
!
sccp local GigabitEthernet0/0
sccp ccm 10.232.5.20 identifier 11 version 7.0
sccp ccm 10.232.5.21 identifier 10 version 7.0
sccp ccm 10.95.159.6 identifier 1 version 7.0
sccp ip precedence 3
sccp
!
sccp ccm group 1
associate ccm 10 priority 1
associate ccm 11 priority 2
!
ccm-manager music-on-hold
!
ccm-manager fallback-mgcp
ccm-manager redundant-host 10.232.5.20 10.232.6.20
ccm-manager mgcp
no ccm-manager fax protocol cisco
ccm-manager config server 10.232.5.21 10.232.5.20
ccm-manager config
!
dial-peer voice 99901990 pots
service mgcpapp
port 0/1/0
!
dial-peer voice 99901991 pots
service mgcpapp
port 0/1/1
!
dial-peer voice 1 pots
service stcapp
port 0/2/0
!
dial-peer voice 2 pots
service stcapp
port 0/2/1
!
dial-peer voice 3 pots
service stcapp
port 0/2/2
!
dial-peer voice 4 pots
service stcapp
port 0/2/3
!
dial-peer voice 5 pots
service stcapp
port 0/3/0
!
dial-peer voice 6 pots
service stcapp
port 0/3/1
!
dial-peer voice 7 pots
service stcapp
port 0/3/2
!
dial-peer voice 8 pots
service stcapp
port 0/3/3
!
dial-peer voice 99901099 pots
service mgcpapp
port 0/1/0
!
dial-peer voice 99901199 pots
service mgcpapp
port 0/1/1
!
dial-peer voice 999010 pots
service mgcpapp
port 0/1/0
!
dial-peer voice 999011 pots
service mgcpapp
port 0/1/1
!
dial-peer voice 18 p

ots
translation-profile incoming PSTN-IN
preference 3
destination-pattern 8T
direct-inward-dial
port 0/0/0:15
!
dial-peer voice 19 pots
preference 4
destination-pattern 8T
port 0/1/0
!
dial-peer voice 20 pots
preference 4
destination-pattern 8T
port 0/1/1
!
dial-peer voice 999 voip
tone ringback alert-no-PI
translation-profile incoming PSTN-IN
preference 3
session target ipv4:10.95.159.6
incoming called-number .T
dtmf-relay h245-alphanumeric
no vad
!
!
!
!
gatekeeper
shutdown
!
!
call-manager-fallback
max-conferences 4 gain -6
transfer-system full-consult
user-locale ES
ip source-address 10.95.159.6 port 2000
max-ephones 46
max-dn 46
system message primary SRST-MODE ENABLE
system message secondary MODO SRST
time-format 24
date-format dd-mm-yy

##########################################################

Thanks a lit to you all....
And Merry Christmas by the way. 

[Roger Kallberg]

From what I can tell your configuration in the gateway for SRST looks good. Have you verified that you have IP set on both protocols on the SRST reference in CM? If you don’t get anything in the debug it would indicate that the phones are not even trying to register.

Apart from this I would recommend you to change your ACL to set the GW and phones in SRST mode to block all traffic to the IPs for the CMs and allow the rest explicitly instead of the way you have it setup now.

Merry Christmas to you as well!

[SNB]

Hi Roger,

Yes, I double check config on CUCM. Same IP addres for SIP and SCCP, but different port (5060 and 2000).

I'll check phone logs to check whether they are trying to register to the SRTS GW.

Kind regards,

SNB.

[Scott Leport]

Hi there,

When I've had these types of issues, e.g the SRST config is correct, but it's still not working, I've found that removing and re-adding the call-manager-fallback configuration has worked for me. Your mileage may vary though and before you try this, it may be worth running a packet capture on the router to check if the SCCP packets are even getting that far.

For exact syntax to run the packet capture on your platform, you can refer to the Packet Capture Config Generator and Analyzer on the Cisco Tools website: https://cway.cisco.com/capture-gen-analyzer/

FYI, an alternative method to test SRST failover as opposed to an ACL would be to configure static routes to your CUCM nodes, pointing to null0, e.g: ip route 10.232.5.20 255.255.255.255 null0. You would also add this in for the other CUCM nodes too. It's become my preferred method of testing failover scenarios, but if your preference is the ACL then suggest you follow Roger's suggestion about re configuring to deny traffic to your CUCM nodes and a permit ip any any at the end of ACL 199.

[Scott Leport]

Hi there,

When I have had these issues, I've found that sometimes removing and reapplying the CM fallback config has resolved the issue. Your mileage may vary though and it may be worth doing a packet capture to find out if there are any SCCP packets reaching the router at all. Config syntax for packet capture config for your platform can be found here: https://cway.cisco.com/capture-gen-analyzer/

An alternative method of testing to ACL would be to configure static routes for your CUCM nodes pointing at null0. For example: ip route 10.232.5.20 255.255.255.255 null0. You would also add in any other CUCM nodes to ensure phones failover to SRST. If your preferred method however is to use the ACL, then reconfigure it as per Roger's suggestion to block traffic towards your CUCM's and have a permit ip any any at the end of your ACL.

[Roger Kallberg]

Agree with you on this. This would be my preferred way to test SRST as well. It’s a cleaner and easier way to understand if you ask me.

[Mohammed al Baqari]

Hi,

Short answer yes this works. Its very standard deployment to register sccp
and sip phones on srst gateway.

First confirm that your sccp packets are allowed to reach the gateway,
confirm that sccp phones are getting IPs, confirm that srst (whether cme or
call manager fallback) is running

***** please remember to rate useful posts

[BalajiSivaraj49175]

ccm-manager fallback-mgcp// CCM-Manager Fallback from the configuration
ccm-manager redundant-host 10.232.5.20 10.232.6.20
ccm-manager mgcp
no ccm-manager fax protocol cisco
ccm-manager config server 10.232.5.21 10.232.5.20
ccm-manager config

[Roger Kallberg]

Those commands are for MGCP configuration and fallback. That is not directly related to SRST configuration or operation. The fallback part is indirectly connected with SRST, to get the control of the ISDN ports to be handed over to local control of the GW in the event the connection to CUCM is lost.

[SNB · Accepted solution]

Hi!

Just to let everyone knows, the problem where in the command "call fallback active"

SRST is now working for SCCP and SIP phones.
I really appreciate all replies.

Kind regards,

Sergio.