GL-X2000 - modem tries to obtain IPv6 address - IPv6 is disabled in config

[nnot]

Why does modem try to obtain IPv6?

(firmware - 4.7.13 - latest stable)

logs:
your sim card may not support ipv6, please contact your carrier
daemon.notice netifd: modem_2_1 (12136): [...] check whether the sim card has obtained an ipv6 address. AT command 'AT+CGPADDR'
daemon.notice netifd: modem_2_1 (12136): [...] requestSetupDataCall QMUXResult = 0x1, QMUXError = 0x1a
daemon.notice netifd: modem_2_1 (12136): [...] try to requestSetupDataCall 60 second later


/etc/config/glmodem

config network 'network_sim1'

option ip_type 'IP'

/etc/config/network

config interface 'wan'

option ipv6 '0'

[charles2]

Hi,

This is a known issue. You can refer to the following thread for more details:

Cellular connection dropping on GL-X2000 Spitz Plus

Bug Report: GL-X2000 — qcm.sh overrides ip_type setting, forces IPv4v6 regardless of user configuration Summary The file /lib/netifd/proto/qcm.sh contains a hardcoded pdp_type='-4 -6' assignment that overrides the user-configured ip_type setting from the network config. This causes the QConnectManager to always attempt an IPv6 bearer setup — even when the user has explicitly set ip_type='IP' (IPv4 only) in the admin panel or via UCI. This leads to a permanent connection failure after Telekom Ge…

On firmware 4.7.13, the workaround is to edit:

/lib/netifd/proto/qcm.sh

Comment out the line:

pdp_type='-4 -6'

Then restart the network service:

/etc/init.d/network restart

Alternatively, you can try a newer beta firmware version, such as 4.8 or 4.9, where this issue should already be addressed.

GL.iNet download center

[nnot]

@charles2

Comment out the line:

pdp_type='-4 -6'

I implemented that before. It is not a solution to the issue I described.

@charles2

Alternatively, you can try a newer beta firmware version, such as 4.8 or 4.9, where this issue should already be addressed.

I've tried 4.9 beta before, it is terrible. I downgraded to "stable" version - 4.7.13.

[charles2]

Hi,

Thank you for the clarification.

Just to confirm one detail: there are two occurrences of pdp_type='-4 -6' in /lib/netifd/proto/qcm.sh. The one inside the IPV4V6 case is expected and should remain unchanged.
The line that should be commented out is the later pdp_type='-4 -6' inside the apn_use block.

Could you please run the following command after applying the change and restarting the network service?

ps ww | grep '[q]cm'

With IPv4-only configured,it would expect the running process to show qcm -4 -n 1.

[nnot]

Hi!

root 1160 S qcm -4 -n 1

[charles2]

Hi,

Thank you for checking.

The output qcm -4 -n 1 shows that QConnectManager is currently running in IPv4-only mode.

To make sure the IPv6 request is no longer being generated during a new cellular connection, could you please reconnect the cellular network once and then run:

logread | grep -Ei 'requestSetupDataCall|ipv6|CGPADDR' | tail -n 30

If there are no new IPv6-related messages after the reconnect, then the current behavior should be normal.

[nnot]

daemon.notice procd: /etc/rc.d/S13gl_ipv6: Command failed: Not found
daemon.info dnsmasq[2892]: compile time options: IPv6 GNU-getopt no-DBus no-i18n no-IDN DHCP DHCPv6 no-Lua TFTP conntrack ipset auth nettlehash DNSSEC no-ID loop-detect inotify dumpfile
daemon.info dnsmasq-dhcp[2892]: IPv6 router advertisement enabled
daemon.info dnsmasq[5695]: compile time options: IPv6 GNU-getopt no-DBus no-i18n no-IDN DHCP DHCPv6 no-Lua TFTP conntrack ipset auth nettlehash DNSSEC no-ID loop-detect inotify dumpfile
daemon.info dnsmasq-dhcp[5695]: IPv6 router advertisement enabled
daemon.info avahi-daemon[6120]: Joining mDNS multicast group on interface lo.IPv6 with address ::1.
daemon.info avahi-daemon[6120]: New relevant interface lo.IPv6 for mDNS.
kern.info kernel: [ ] IPv6: ADDRCONF(NETDEV_CHANGE): wwan0_1: link becomes ready
daemon.notice netifd: modem_2_1 (7359): [] requestSetupDataCall WdsConnectionIPv4Handle:
IPv6: ADDRCONF(NETDEV_CHANGE): wwan0_1: link becomes ready
daemon.info dnsmasq[17686]: compile time options: IPv6 GNU-getopt no-DBus no-i18n no-IDN DHCP DHCPv6 no-Lua TFTP conntrack ipset auth nettlehash DNSSEC no-ID loop-detect inotify dumpfile
daemon.info dnsmasq-dhcp[17686]: IPv6 router advertisement enabled

[charles2]

Hi,

Thank you for providing the log.

The log now shows requestSetupDataCall WdsConnectionIPv4Handle , which indicates that the cellular data connection is being established as IPv4 only. We do not see a new IPv6 data call request in the log you provided.

Based on the current log, we do not see any new IPv6 data call requests from the cellular connection.

The other IPv6-related entries, such as IPv6 router advertisement enabled , the Avahi lo.IPv6 message, and ADDRCONF(NETDEV_CHANGE) , are generated by the router's local IPv6 stack/services and do not indicate that the modem is requesting an IPv6 cellular connection.